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The early Islamic caliphate from the first Muslim conquests in the Middle East until the mid-tenth century was the richest and most populous state in the whole of Western Eurasia. Globally, only the almost contemporary Tang Empire in China could rival it for the size of its cities, wealth of its people, the scale of its trade and manufacturing and its cultural output. In this chapter, I shall try to suggest some of the reasons for this prosperity in the first three centuries of Muslim rule and the seismic changes which occurred during the tenth and early eleventh centuries. There is a large and growing literature on this subject, combining archaeological and written evidence and at least one large volume could be written on the subject. This chapter can only attempt to sketch the general arguments and point to some of the most important studies and it cannot be a comprehensive survey.
Estimating the comparative size of the early Islamic economy in the absence of comprehensive statistical data can only be conjectural. Perhaps the clearest evidence comes from the cities. Estimates suggest that Baghdad in the ninth century probably had a population of between 250,000 and half a million at a time when it is unlikely that Paris or London could boast a population of 10,000. Coined money, gold dinars, silver dirhams and copper fulūs, millions of them, were used to collect taxes, pay soldiers and buy and sell food and consumer goods. It has been estimated that there are some half a million silver dirhams surviving from the ninth, tenth and eleventh centuries, three quarters of them found in deposits in northern Europe (Kovalev, 2007). These can only have been a small percentage of the total coins in circulation at this time and the writings of the period are full of references to money, collected, spent, given away, stolen or hoarded. The markets of the big cities stimulated agricultural and manufacturing in the wider countryside and merchants grew rich by importing exotic, status-enhancing luxuries.
Of course we do not have the sorts of evidence which drive economic history in the modern period, there are no accurate figures of population, no systemic collection of income data, no possible measurements of gross domestic product. Instead, we have to rely on comments and anecdotes in historical writings by authors for whom economic history, as we might understand it, is not the centre of their interests. More revealing are the writings of the Arab geographers of the late ninth and tenth centuries with their descriptions of roads and countries, products and peoples. The Ṣūrat al-ard of Ibn Ḥawqal is perhaps the most aware of the working of economic factors in the lands he visited.
Equally if not more important is the material evidence. Numismatics clearly have a central role. The number of coins, gold dinars, silver dirhams and copper fulūs which survive from this period is enormous but they alone can only be one part of the story: very fine coinage does not by itself indicate an economic activity on a wider scale. More revealing is the archaeological evidence. City surveys of Samarra, Marw, Rayy, Paykent and numerous others tell their story of expansion or decay. Surveys of rural areas can show us the extent of cultivation and settlement and surveys from the hinterland of Baghdad, the Middle Euphrates valley and the Syrian steppe lands are all crucial to our understanding.
By using textual, numismatic and archaeological evidence together, we can piece together something of the structure and extent of this remarkable economic efflorescence, and, on a more sombre note, some of the reasons for its apparent retreat after two centuries.
Fundamental to our understanding of the comparative size and complexity of this economy is the fact that the early Islamic state was the only post-late antique polity which preserved a structure of public taxation, collected in coined money and distributed by the state and its agents to certain select groups, most obviously the military and the bureaucrats who ran the system, in the form of regular salaries. This, in turn, created the demand for goods and services in the economy which formed the driver of economic development and diversification.
As described elsewhere in this volume, the initial Arab military conquests were followed by waves of immigration from the Arabian Peninsula, those from western Arabia and Yemen tended to head for Palestine, Syria and Egypt, those from Central Arabia and the lands bordering the Gulf, to Iraq. In areas like Iraq and Syria, these new arrivals may have amounted to 10 or 15% of the total population.
Within a few years of the first conquests, it became important to decide how these new arrivals were to integrate into the local society and economy. Although there were village people from highland Yemen and Oman, most of these incomers came from pastoral bedouin backgrounds. They were unused to ploughing the land and cultivating palm-trees and they probably did not want to undertake this hard menial work either. Nevertheless, some of the conquering Arabs demanded that the lands be divided up between them so that they could settle and live off the labour of the existing local inhabitants.
This option was rejected. It was pointed out that each of the conquerors would enjoy the labour of just three local peasants, hardly a luxurious lifestyle. Inevitably, they would mingle with the local people, losing their identity, their elite status and even their Islamic religion. Instead, the controlling ruling group in the capital Medina, the city of the Prophet, led, are told, by the second caliph ʿUmar, made a radical alternative plan, one which was to affect the history of the Middle East for centuries to come and which meant that the Arab settlement of the Middle East was to be very different from the Germanic conquests of Western Europe in the fifth century where the invaders were soon absorbed into the local population.
The rulers of the new empire decided that the Arabs were to be settled in garrison cities (miṣr, pl. amṣār) where they could be kept, ready for war and further conquests. They were to live off revenues collected from the subject population in the form of taxation. At first, some of this taxation was to be collected in kind, wheat, oil and so on, but quite soon, certainly before the end of the Umayyad period, it was arranged that tax should collected in coined money. At the same time, the Arabs in the cities were to be paid in this same money. The scheme was first rolled out among the settlers in central and southern Iraq where the two garrison cities of Kufa and Basra were established, but it was later adopted in other provinces where there was substantial Arab settlement. Other garrison cities followed, Mosul in northern Iraq, Fustat (Old Cairo) in Egypt, Qayrawan in Tunisia, while in the east garrison cities were established, in Shiraz in southern Iran and Marw (Turkmenistan) on the northeast frontier. In all cases, the model was similar. Tax revenues were brought to the cities and dispensed to the conquerors as cash wages.
The system had important consequences far beyond the mechanics of paying the army, especially because of the large numbers of the beneficiaries, 60,000 we are told in Kufa, 80,000 in Basra during the early Umayyad period, and that was just the adult males. Soon, they were joined by converts to Islam among the subject population. Three things were needed to make this system work, the measurement of land to assess tax, the production of large quantities of cash to pay it and literate and numerate administrators to run it. This, in turn, led to the establishment of a class of salaried soldiers and bureaucrats, people with more than enough money for basic subsistence, people with money to spend on luxury foods, clothes to show their status, perfumes to adorn themselves with and ultimately education and books. This fiscal structure was fundamental to the growth of the wider economy and the rich and varied cultures it sustained.
Paying the army was by far the most important function of the administration. In the first three centuries of Islam, soldiering became increasingly professionalized. New technologies of warfare, like mounted archery in the third/ninth century, meant that the military were increasingly professional and they demanded to be paid on a regular basis and woe betide any ruler who could not find the money. Bureaucrats grew wealthy managing the payment and merchants came from all over the Muslim world to offer their goods in the great markets of Baghdad and other expanding cities.
The military may have been the most conspicuous sector of the population with money to spend but they were by no means the only ones. In an important article, Pamuk and Shatzmiller (2014) have argued from Iraqi and Egyptian evidence that wages for labourers were consistently above the costs of a “bare bones” basket of food stuffs in the period from c.700 to c.1000 CE. They suggest that this was a result of demographic decline following the Justinianic plague of 540 and its recurring outbreaks. Adapting the comparative data from the Black Death of 1347–49, they argue that workers benefitted from a labour shortage to increase or at least maintain wages. It also encouraged female participation in the work force which again increased family incomes and specialization in the labour market. Along with this, there was essentially free movement of labour in most areas with the possible exception of Egypt. Many workers were not tied to their jobs and could move when new opportunities of work, great building projects like the Round City of Baghdad or new farming openings in the Jazira, appeared. This, in turn, expanded the markets for goods and services. Building labourers did not grow their own food; they bought it in urban market. The Pamuk-Shatzmiller argument is based on evidence in chronicles and other texts, supplemented in the case of Egypt by papyri and the Cairo Geniza, but such evidence, while mostly reliable, is not comprehensive. However, if the argument is broadly correct, it explains the development of demand in the economy which extended far beyond a privileged elite.
Supplying food for the new and expanding cities of the early Islamic world was one of the major driving forces in the economic development of the period. While the food supply of ancient Rome has attracted considerable scholarly interest and the food supply of Constantinople has also been investigated, there has been virtually no research on the provisioning of the great early Islamic cities. If a city like Baghdad had half a million inhabitants, a plausible estimate, each of whom could aspire to have at least one meal a day, the food supply must have been a huge and complex operation. We can however be reasonably certain of two things, first that it must have led to the construction of complex and widespread networks and second that these networks were fairly efficient in that we rarely have mention of serious food shortages before the fourth/tenth century. The food supply was not, unlike that of ancient Rome with its government-run system of annona, organized by the sulṭān. It seems to have been essentially a private enterprise system. There was no general-free handout of food: people paid for what they ate and, fortunately for them, the supply was generally cheap and reliable.
In the account of the foundation of Baghdad in al-Ṭabarī’s Ta’rīkh, al-Manṣūr is shown to be well aware of the importance of food supply. He describes how his new city will have access to the grain supplies of the Jazīra which can reach the capital by the Tigris and Euphrates rivers and the dates which can be brought up along the southern river systems from Basra and southern Iraq. He also talks about routes for goods from India and China, coming up the Gulf. These economic networks led to the creation of a Greater Mesopotamian economic area. It was above all in this area between c.700 and c.900 that agriculture expanded into areas in which there had been little or no farming. I use the term Greater Mesopotamia to include the valleys of the Euphrates and Tigris rivers between the great bend of the Euphrates in northern Syria and the head of the Gulf. It also includes the lands of Khuzistan, now in southwest Iran. This area was the bread-basket of the caliphate and the generator of a large part of its tax revenues. It was marked by a core of easily irrigated lands along the great watercourses and a more extensive periphery which could be brought under cultivation by investment in favourable circumstances and when the market encouraged it, but left to pastoralists and herdsmen when a precarious economic situation or political insecurity was discouraging.
The archaeological evidence for the expansion of settled agriculture in this area from the middle Umayyad into the early ʿAbbasid period is consistent and convincing. The results of this can be seen in the traces on the landscape recovered by archaeological survey. In 1965, Robert Adams published The Land behind Baghdad in which he used the distribution of pottery sherds to reconstruct the history of human occupation in the Diyala river valley to the northeast of Baghdad. Although some of his dating has been questioned, it is clear that the greatest expansion of settled agriculture occurred during the late Sasanian and earliest Islamic periods. Surveys from the Middle Euphrates, the Khabur and Balikh valleys and the plains watered by the Dujayl (Little Tigris) in Khuzistan all point in the same direction; new canal systems led to the foundation of new villages and individual farms. This expansion is confirmed in the written sources, especially al-Balāḍhurī’s Futūḥ al-Buldān, in which the author describes how the elite of the Umayyad state invested in digging new canals and encouraging settlers to farm the lands along them. This was perhaps a two-stage process. In the Umayyad period, the initiative was taken by the elite; in the early ʿAbbasid period, it looks as if smaller scale entrepreneurs were taking the lead. We can see this in the case of the settlement at Hiṣn Maslama in the Balīkh river valley, now in northern Syria. As the name suggests, this was an elite fortified settlement established by the Umayyad princes Maslama b. ʿAbd al-Malik. It was a classic Umayyad qaṣr, a square enclosure within well-built fortified walls. In the early ʿAbbasid period, the walls were breached and unplanned settlement spread out beyond the old fortifications into the surrounding plain.
The Islamic conquests made a fundamental change to the economic gravity of the Middle East. The unification of the Roman and Sasanian sectors of Greater Mesopotamia led to an economic integration of the area which had not been possible before. The grain-growing lands of the northern Jazira had access to the rapidly expanding urban markets of Central and Southern Iraq. With grain came the products of the northern uplands, fruits and honey from the Anatolian mountains, animal products from Azerbayjan and Armenia.
The rise of Greater Mesopotamia contrasted with contraction and abandonment of other areas. The areas which benefitted were those which had access to the river systems and markets of Greater Mesopotamia but those which were cut off failed to thrive. The most obvious of such areas were the inland parts of Syria and Palestine. There are unmistakable signs of economic distress in inland Syria and Palestine from the beginning of the third/ninth century. The archaeological evidence shows many examples of settlements large and small, which had survived the Muslim conquests, flourished in the Umayyad period but withered and died after the year 800. From the abandoned villages of the limestone hills of Syria in the north to the Negev Desert in the south, the evidence is plain and the silent witness of ruined houses and churches fills the landscape. No new towns were developed in greater Syria after Ramla in the second/eighth century. The urban centres which survived were coastal towns, subsidized by the sulṭān to defend against Byzantine attacks and centres of government, like Tiberias, capital of the province of Jordan which seems to have thrived until the fifth/eleventh century.
The reasons for this are probably twofold. The first was transport. Moving large quantities of goods from inland Syria and Palestine overland to the growing towns of Greater Mesopotamia was difficult and uncompetitive. The second is that the new ʿAbbasid sulṭān no longer recruited and paid men from the great Syrian tribes like Kalb who had sustained Umayyad rule. They must have been the customers who bought in the Umayyad period sūqs attested by archaeology in towns like Palmyra-Tadmur and Scythopolis-Baysān. It was the smaller towns along the desert margins in the Hawran, the Jordanian steppe and the Negev which suffered worst and urban life in these areas almost completely disappeared.
New areas were certainly being brought under cultivation but this was not the only new development. In 1983, Andrew Watson published a book called Agricultural Innovation in the Early Islamic World. In this, he challenged an established assumption that the coming of these nomad conquerors led to a decline, even devastation of rural agricultural communities as more and more villages and small towns were abandoned and the flocks and herds of the pastoralists roamed where they would. The abandoned sites of these rural settlements could be seen throughout the steppe lands Syria and Palestine, their gracious but melancholy ruins testifying to a lost era of quiet prosperity. Watson argued that there was another, different story to tell. The coming of Islamic rule stimulated the development of new crops as old barriers to diffusion were broken down. Rice and the hard durum wheat used to make pasta spread through the Muslim world and then across the Mediterranean to southern Europe. It was a tale of innovation and enterprise.
This hypothesis proved controversial and historians have been keen to point out that things were not quite so simple. Many of the crops which Watson saw as new were in fact already to be found though not widely distributed. The debate rumbles on but the basic conclusion is that the coming of Muslim rule enabled and encouraged the much wider diffusion of new crops. More recent research has begun looking at agricultural techniques, especially technologies of irrigation like underground qanats. Did these technologies spread along with new crops?
The growing demand led to increased specialization and the development of cash crops. Richard Bulliet in his Cotton, Climate and Camels in Early Islamic Iran (2005) has shown how a “cotton boom” developed in central Iran when entrepreneurs established new villages and brought water to barren lands. The cultivation of sugar cane brought not only a new cash crop but also a new industrial process.
The economic and intellectual flourishing was dependent on freedom of movement. Merchants travelled with goods to sell, artisans and labourers moved to find jobs in new construction projects, students and scholars travelled to sit at the feet of great masters. Following another pioneering work by Bulliet, The Camel and the Wheel (1975), it is now clear that wheeled vehicles disappeared from the roads of the Islamic Middle East. Instead, it was caravans of pack-animals, horses, mules and, above all, camels which did the heavy lifting. Wheeled vehicles in the twentieth century world have had a profound effect on the shape and design of roads both within and between cities. The disappearance of such vehicles in Late Antiquity and had an equally profound effect. The carefully constructed roads of the Roman period with their stone surfaces and masonry bridges fell into disuse because pack-animals did not need them. City streets and lanes in markets could become narrower, where people and animals pushed past each other.
Although the camel caravan was universally used, water transport was also important. The Nile was the transport as well as the irrigation backbone of Egypt. In Greater Mesopotamia, the Euphrates and Tigris rivers were essential for the transport of goods. The Euphrates was navigable downstream from Bālis, described as the furda (entrepot) of Syria where goods could be imported from Aleppo and the Mediterranean coast. The Tigris was navigable from Jazīrat Ibn ʿUmar (now Cizre in Turkey, close to the Syrian border). More surprisingly, we are told of navigation on the Khabur, a northern tributary of the Euphrates, which can only have transported small, shallow draft vessels. We have very few practical details about the water transport but evidence from the nineteenth and early twentieth centuries suggests that this traffic was mostly one way: goods were loaded on boats or rafts and floated down to the markets of Baghdad and southern Iraq where they would be broken up and the wood sold. We can see the emergence of towns along the river banks to handle this trade. Most important of these was Raqqa, normally thought of as a military political centre, but which probably also handled the grain trade of the Jazīra. The history of two smaller towns shows how this river traffic generated urban settlement. Jazīrat Ibn ʿUmar was developed by a local tribal chief, al-Ḥasan b. ʿUmar al-Taghlibī at the point where the Tigris cuts through the Anti-Taurus Mountains and enters the flat plains of northern Iraq and the river becomes navigable. From here, the products of the forests, timber, honey and wax could be exported south. Al-Raḥba, sometimes called Raḥbat Mālik b. Tawq (d. 260/873–874) after the Taghlibī chief who developed it, was also called simply al-Furda, the river port. The town lay on the right bank of the river and flourished from the trade. Probably in the eleventh century, however, the riverbank site was abandoned and a new fortress was built on the escarpment at the edge of the desert. Defence had become more important than trade as the decisive factor in siting the settlement.
In Central Asia, the mighty river Oxus provided the easiest way to traverse the Black Sand and Red Sand deserts. The river was navigable from Termez to Khwarazm but we have little information about how it was used. Faḍlān in his account of his travels mentions that he took a boat from the river crossing at Amul near Bukhara to Khwarazm of his way north.
If the provision of basic food supplies was fundamental to the economy, it was consumer goods, the little luxuries of life, which provided the icing on this cake. The goods were important not only for the pleasure they gave but for the status they generated. Conspicuous consumption was the order of the day. Fine textiles were the most important goods for personal display but also the least visible in the historical record. We have virtually no material examples, just descriptions in texts. As well as the fabric themselves, there were dyestuffs. Bright, clear colours demanded trade in the natural products which provided them, indigo from the Jordan Valley for the blues, beetles from Armenia for crimsons and so on. There were exotic ceramics, including Chinese imports as found in the famous Belitung shipwreck, imports which stimulated local artisans to imitate them and develop the almost metallic hues of classical Muslim lustre ware. Then, there were raw materials from distant lands like rock crystal from far-off Madagascar to be carved into exquisite vases.
Exotic foods were very much part of this demand. We have descriptions of feasts but also contemporary recipe books with ingredients like cloves from Spice Islands of Indonesia. The complexity of this market is shown by the demand for dried fruit, especially dried melons, from Central Asia. It is possible to grow melons around Baghdad and plenty of sunshine to dry them in, but the melons of Marw were more sought after to the extent that it was worth transporting them more than a thousand miles to Baghdad where they would command the best prices. And then there were perfumes, both incenses to burn and unguents to adorn the body. Most of these told a story of long-distance trade from exotic and scarcely known countries where Muslims scarcely ventured.
The early Islamic was a period of urban expansion. Cities grew as centres of economic activity and political power, often at the expense of smaller towns in their areas. As Fanny Bessard has shown in her Caliphs and Merchants (2020) great merchants became the social and political as well as the economic leaders of the caliphate. This mass of comparatively affluent and comparatively educated people were also the consumers of culture, above all of writing and books. The new technology of paper making was embraced with enthusiasm, enabling the democratization of literature, the commercialization of book production. Baghdad in the ninth century was probably the first society on planet earth in which an author could make a living, if only a precarious one, by writing books and selling them to public in the hundred bookshops that are noted in a single quarter of the great city. As Beatrice Gruendler has shown in her recent work The Rise of the Arabic Book (2020) has explored the publishing industry of the time. None of this would have happened without a thriving economy which put money into men’s sleeves and purses.
There is little evidence that the government directly encouraged trade by making trade agreements with neighbouring powers or maintaining the infrastructure of travel. There were other areas in which the sulṭān played a less active but still vital role. The most obvious of these was the keeping of routes safe from brigands and robbers. It also kept travelling merchants safe from tax collectors. There is little or no evidence of internal taxes on the movement of goods before the fourth/tenth century; the caliphate was a single market. Nor is there any evidence for the taxation of transactions in the market. The sulṭān made money from markets by charging ground rents on shops. This benign, light touch, fiscal regime allowed trade to flourish.
The second was that the sulṭān itself, whether in Abbasid Baghdad or Fatimid Cairo, formed the most important market for goods and services. Rich textiles and other objects of desire were sourced from all over the caliphate to show prestige and reward service. Where the caliphs led, their elite supporters followed. But perhaps most important was the role of the sulṭān in pumping money into the economy by paying salaries to soldiers and others. It was this that created a reliable continuing market to encourage investment.
The third way in which the sulṭān supported trade was by the provision of coinage.
Coins are one of the commonest and most visible signs of the economic vitality of this period. The Muslims inherited a tri-metallic system of coinage, gold denarii/dinars and copper folles/fulus in the ex-Byzantine lands and silver drahms/dirhams in the Sasanian territories. After the currency reforms of ʿAbd al-Malik at the end of the first/seventh century, these two zones were more or less integrated, dirhams were regularly used in the West, while dinars were certainly an accepted, if less widely used, currency in the East. The effect of this must have been to facilitate long-distance trade between different areas of the caliphate, a process encouraged by the development of simple financial instruments like the suftaja and the ṣakk which allowed the movement of wealth without the actual transport of large quantities of coin. Of course, the system was not entirely stable. The dirham/dinar exchange rate fluctuated from about 12:1 in the earliest Islamic period to about 20:1 by the fourth/tenth century. Furthermore, the developing silver “famine” meant that dirhams were increasingly and openly adulterated with lead and other metals leading to “Black dirhams” especially in Khurasan. Despite these problems, however, Islamic currency facilitated exchange over wide areas and, despite the emergence of new dynastic polities from the four/tenth century with rulers inscribing their own regional titles on their coins, money seems to have moved freely throughout, measured by purity and weight more than face value.
The proper functioning of the sulṭān was the necessary framework for the development of the economy but growth was generated by individual and private initiatives.
The coming of Muslim rule had a profound effect on patterns of trade throughout early medieval Eurasia. There were major ruptures. The decline of trans-Mediterranean trade which had flourished in classical antiquity had begun before the Muslim conquests but they certainly accelerated it. The Sea itself became a conflict zone and large-scale regular trade became impossible, though it is clear that trade in slaves from Western Europe continued to be the backbone of a smaller but continuing commerce, while the fact that cloves and spices from Indonesia were still to be found on the tables of Emperors and Popes points to the survival of some luxury trade at an elite level. The olive-oil of Tunisia was no longer shipped to Constantinople and points east in the distinctive African red-slip pottery which is so commonly found in archaeological sites of the period. Not only did the trade in oil stop but so did the manufacture of the ceramics which contained it. The surplus grain from Egypt, which had sustained the populations first of the city of Rome and then Constantinople, and provided the backbone of Mediterranean trade, was cut off. Instead, the surplus was shipped via the re-opened Trajan’s canal from Cairo to the Red Sea to the burgeoning Holy Cities of Mecca and Medina.
In the east too, trade routes were changed though the process was slightly later. The economic importance of the fabled “Silk Road” from Chine to Persia and Rome has probably been exaggerated but it was nonetheless significant and it supported a vibrant commercial and cultural network. Those great middlemen of the early Middle Ages, the Soghdian merchants of Central Asia, became rich and prosperous. Just as pilgrims from Western Europe continued to travel to the Holy Places in Palestine after the fall of the Western Empire so Buddhist pilgrims from China made the long and arduous journey through the central Asian deserts and the mighty Hindu Kush mountains of Afghanistan to visit the sites of the Buddha’s life in India. By the year 800, all this had changed and the overland silk route had become impractical, partly it would seem, because of the prolonged An Lushan rebellion on western China.
While some of the old patterns declined, new trade routes were developed in response to the growing size of Middle Eastern markets. Trade with the China and the Far East continued but in a very different form. There were trade links between the Mediterranean world and India which were well established in Roman times and Persians conducted some trade in the Sasanian period, though the details are hard to recover. From the second/eighth century however, Indian Ocean trade began to expand. More and more Muslim merchants, based in the Gulf at ports like Basra and Sīrāf, began to sail as far as China where there was a large Muslim commercial colony in Canton by the mid-third/ninth century. It was not just the routes which changed, from overland to maritime, but the nature of the goods. It would seem that silks ceased to be the dominant trade goods, not least because the inherent dampness of travel by sea made them unsuitable. Instead, the main goods were spices, the ingredients for perfume (musk, ambergris) and ceramics. The evidence for the trade in Chinese ceramics has been spectacularly confirmed by the Belitug shipwreck with its 60,000 pieces, apparently destined for the Middle East market. This, in turn, spurred potters in the Islamic world to rise to the challenge and develop new glazed wares of their own.
Another area of new trade was the Russian and Scandinavian north. From the third/ninth century, an important new trade route developed though the river systems of what is now Russia. This led from the Baltic and Scandinavia to the markets of Central Asia in the lands ruled by the Samanid dynasty. The goods traded were furs and above all slaves, especially females, trafficked from the Slav lands. In return, the Muslim merchants paid in silver Samanid dirhams, hundreds of thousands of them. They do not seem to have been spent but rather stored in hoards where they lay untouched. These hoards are found as far away as the Isle of Skye of the west coast of Scotland. Apart from the famous, vivid travel account of Ibn Faḍlān’s voyage to the Volga basin, we hear little about these from written sources but the coins reveal the size and extent of this trade. And it had long-term consequences: it brought Scandinavian merchants, who seem to be referred to as Rūs, into what is now Ukraine where, by the year 1000, they had established the principality of Kiev and converted to Greek Orthodox Christianity. On the other side, it seems to have drained northeastern Iran of silver contributing to the silver famine. By the early fifth/eleventh century, this trade had essentially dried up. The routes from north-west Europe to the Middle East now led through the Mediterranean.
The economic crisis of Iraq in the fourth/tenth century led to a major shift in the patterns of global trade. By the year 1000, the cities of Greater Mesopotamia had ceased to be the most important market for imported goods and in the first half of the fifth/eleventh century, the balance of economic power had shifted to Egypt and, to an extent, the cities of the Iranian plateau like Isfahan and Rayy. The rise of the Egyptian market meant that the maritime trade of the Indian Ocean basin, including the East African coast, shifted from the Gulf to the Red Sea. It was also the background to the appearance of western merchants, Franks, in the ports of the eastern Mediterranean. They mostly came from Italy, Amalfi in the south and, a bit later, Venice, Pisa and Genoa in the north. They came in search of consumer goods, fine textiles and, above all, pepper and spices, transhipped through Cairo and Alexandria from the Indian Ocean areas. The driving force of this expansion was the growing economy of north-west Europe, the opening up of new silver mines. This means that, for the first time since antiquity, Western Europe was a market with sufficient surpluses to generate a regular market. The great expansion of trade at the time of the Crusades in the twelfth and thirteenth centuries was the acceleration of a pattern which had begun in the eleventh.
If the Red Sea and the Mediterranean were increasingly the scene of a lively commerce in the late tenth and early eleventh centuries, the position was very different in Greater Mesopotamia. In a real way, this system here had depended on a sort of virtuous circle. Government expenditure encourages spending and investing and the economy expanded. But it was also vulnerable. In a sense, it was very highly leveraged. A risk assessment would show small number of bad years of political disturbance or warfare could do unsustainable damage and in the first half of the tenth century, bad years came thick and fast. Civil wars and social rebellion destabilized the tax system and the military, concerned above all to secure their pay, showed no compunction in deposing and murdering both caliphs and bureaucrats.
In economic terms, these changes led to important changes in the patterns of settlement and economic activity. One of these was the contraction of agriculture in the lands of Greater Mesopotamia. Baghdad, and to a lesser extent other cities, no longer offered the open and dynamic markets of the time of the military/bureaucratic state. They still existed as medium-sized local centres but as rulers and their entourages moved from one castle to another, and fought each other for control of a decreasing resource base, the market which had encouraged the investment of the earlier period withered. This is noticeable in the changed pattern of investment of surplus wealth. In the late Umayyad and early ʿAbbasid periods, the elite invested the profits of office and warfare in landed property, buying up and developing estates. From the mid-tenth century, however, we see anecdotal evidence of elite figures hiding their wealth in the form of cash and treasure or simply burying it in the ground. Land was no longer considered a safe repository for wealth. Throughout the area, irrigation canals were abandoned, settlements moved from the riverain plains to defendable high ground. For the first time, we see internal customs posts set up by local rulers to extract tolls from merchants travelling from one part of the Muslim world to another. Finally, it was during this period that ʿAbbasid Greater Mesopotamia lost its position as the economic and later cultural power house of the Islamic world to Fatimid Cairo. To take just one example, the production of fine lustre work ceramics moved from Iraq to Egypt as the craftsmen migrated, taking their expertise with them, in search of the new elite markets.
The flowering of early Islamic society and culture was based on a thriving and varied economy. Without this widespread prosperity, the arts and sciences would not have flourished and Islamic civilization might have looked very different. But if it was the beginning of one story, it was the end of another. The Abbasid caliphate was the last of that great series of ancient empires which stretched from the Kings of Sumer and Akkad in the third millennium BC, through the Assyrians, Babylonians and Persians. In the tenth century, this came to an end. Never again would a power based on the wealth of greater Mesopotamia power lead the world in richness and culture.