The level of violence witnessed during the Thirty Years War is a gruesome illustration of what historians have labelled the ‘western way of war’. Gustavus Adolphus, like Belisarius, William the Conqueror and Henry V before him, understood that a decisive engagement on the battlefield was the surest way of furthering his political aims. And while Swedish forces did manage to kill one-third of their imperialist enemy, this understanding cost Gustavus his life and the lives of one-third of his army at Lützen. When western armies made war against one another, such casualty figures were not unusual.
As described in the previous volume, Warfare in the Ancient World, Europeans have practised a form of organized violence that placed a premium on decisive battle since classical Greek times. Greek hoplites specialized in a form of brutal confrontational combat that beat down or carved up their enemies, often against numerically superior armies. The Romans continued and perfected this lethality in arms. Roman legions conquered and protected a Mediterranean empire that lasted half a millennium. But the Western Roman Empire finally succumbed to internal rot and external invasion and migration, while the Eastern Roman Empire continued as the Byzantine Empire for another thousand years.
The Byzantine martial experience built upon the traditions of the late Roman Empire, though there was a change in emphasis from infantry to cavalry. Justinian’s commanders, Belisarius and Narses, used Byzantine combined arms to conquer a new Mediterranean empire. Here, this Byzantine brand of western warfare blunted Persian advances at Dara in Armenia and destroyed Vandal and Frankish aspirations at Tricameron in north Africa and Casilinum in Italy. At Casilinum, Byzantine troops slaughtered their Frankish foes nearly to the man.
In western Europe the Germanic armies, which filled the power vacuum left by the collapse of the Western Roman Empire, represented a decline in martial capabilities. By the time the end came, centuries of ‘barbarization’ had eroded the combat efficiency of the Roman legion, and with the end of the professional army came the end of well-articulated heavy infantry, replaced by the Germanic militia system and its unarticulated battle squares. These Germanic warriors could fight with great ferocity, as the battles of Adrianople and Châlons illustrate, but they initially lacked the military and social organization and support to mount the kind of large-scale campaigns witnessed in the classical period.
Over time, old Roman territory and Germanic tribal lands were transformed into Germanic kingdoms, with the Franks in what was Roman Gaul becoming the pre-eminent regional power. The most successful Frankish commanders adhered to the doctrine of decisive battle in the western tradition. Charles Martel soundly defeated an aggressive Muslim raiding expedition at Tours using a bold fighting strategy and confrontational tactics, killing the Muslim governor of Spain and securing a new Frankish dynasty. His grandson Charlemagne undertook fifty-four military campaigns and expanded Frankish hegemony into northern Spain, Brittany, Bavaria, and Frisia and Saxony. Charlemagne well understood the value of ‘spear-tip diplomacy’, and used the threat of military engagement and annihilation to enforce his political will.
After Charlemagne’s passing in 814, a ‘Second Age of Invasions’ besieged Christian Europe. Magyars and Vikings attacked from the east and north, plunging the continent into over two centuries of chaos. The Magyar threat was finally extinguished by the German king Otto I along the banks of the Lech River in a set-piece battle which pitted the flower of Catholic chivalry against skilled central Asian horsemen. Otto’s military victory brought profound political changes. After the destruction of the Magyar army, the remnants of the raiders converted to Christianity and created the kingdom of Hungary, while the feat ensured Otto’s rise to holy Roman emperor. The Vikings, like the Magyars, were master raiders, preferring ‘smash-and-grab’ tactics over decisive battle. But as the Viking age wore on, some Scandinavian commanders adopted the latter brand of warfare while campaigning. One of the period’s greatest warriors and kings, Harald Hardrada, used decisive battle effectively to secure political position and military reputation. Trained in the ‘western way of war’ while serving as captain of the Varangian Guard in Constantinople, Hardrada would risk it all and fail seeking a decisive engagement against Anglo-Saxon king Harold Godwinson at Stamford Bridge. His defeat there ended his life and the Viking age of invasion, and weakened his opponent Godwinson enough that another political opportunist and brilliant commander, William, duke of Normandy, could seize the initiative and take England from the Anglo-Saxon ruler at the battle of Hastings.
By the eleventh century, the Normans emerged as the pre-eminent military power in medieval Europe. Duke William of Normandy became King William of England because of decisive battle. His one-day victory at Senlac Hill killed the English king and broke the back of the English army, paving the way for a successful occupation. In Italy the Norman adventurer Robert Guiscard fought his way into title and carved out a dukedom at the expense of papal and Byzantine lands. Guiscard’s mastery of organized violence is illustrated by his overwhelming victory over Byzantine forces at Durazzo, a victory which witnessed the foolhardy gallantry of the Varangian Guard and their extermination by Norman combined-arms efforts. Norman fortunes continued to grow in southern Italy, while other Normans sought fame and fortune ‘taking up the cross’ in the Holy Land.
Military success and failure during the crusades was also a product of decisive battle. When the Byzantine emperor Romanus IV Diogenes sought battle against the Seljuk leader Alp Arslan at Manzikert, he was seeking a military solution to the Seljuk threat. His defeat there precipitated the loss of most of Anatolia, a fatal weakening of the Byzantine Empire, and became the casus belli for the crusades. When the Catholic armies answered Pope Urban II’s call to arms in 1095, the Norman-led armies that crossed Anatolia and shattered the Seljuk Turks at Dorylaeum brought with them western-style confrontational tactics, tactics which relied on the primacy of heavy cavalry shock combat. Most historians would agree that the appearance of the second crusader column saved the entire expedition and that the victory at Dorylaeum was a near-run thing. Still, the destruction of the Seljuk force allowed Roman Catholic crusaders to carve out numerous principalities and usher in a 200-year occupation of Syria and Palestine.
Not all of the practitioners of the ‘western way of war’ were Christian. The great Muslim general Saladin showed his mastery of decisive battle at the Horns of Hattin, destroying the main crusader army (complete with its elite Templars and Hospitallers) in the Holy Land and taking Jerusalem back for Islam. This Christian reversal led to the formation of the Third Crusade, where King Richard I of England met and vanquished Saladin’s troops near the Forest of Arsuf. This battle, though tactically decisive, did not alter the strategic balance of power enough in Palestine for the English king to even attempt a siege of Jerusalem. With Richard’s failure to take back the Holy City for Christendom, the tide had turned against the crusaders in the Levant. Islam would slowly take back the Holy Land in the thirteenth century, oblivious to a new and more dangerous storm from the east – the Mongol invasions.
Genghis Khan forged a military machine in the thirteenth century that secured the largest contiguous land empire in human history, stretching from Korea to Poland. The success of the Mongol art of war relied on the decisive cavalry engagement and a keen understanding of the enemy’s tactical predilections. Mongol warriors were masters of both manoeuvre warfare and ruse, and used the reputation of steppe warriors as ‘hit and run’ specialists against civilized armies. When Mongol cavalry engaged Duke Henry’s Christian forces at Liegnitz, they were counting on the knights’ penchant for confrontational battle to work against them. The Mongols were not disappointed. Wheeling and retreating in front of the Christian lines, the Mongol horse archers goaded the Christian heavy cavalry into pursuit, opening a gap and the opportunity to strike hard and finish off the western army. At Sajo River the Mongol commander Batu Khan took the measure of King Bela of Hungary, and destroyed the Christian army using brilliant combined-arms attacks. Both of these decisive battlefield victories allowed the Mongols to extend hegemony into eastern Europe, with the steppe warriors maintaining a stranglehold on Russia for 100 years before the grand prince of Muscovy Ivan ‘the Great’ defeated them at the battle of Kulikovo Field in 1380.
The Mongols enjoyed similar success in south-west Asia before the Mamluks blunted their progress at Ain Jalut, south of Lake Tiberias. Mongol penetrations into the Islamic west destroyed both the Ismaili Order of the Assassins in northern Iran and the Abbasid Caliphate in Baghdad in 1258, and, pushing west past the Euphrates, threatened the Mamluk sultanate in Cairo. The cavalry of the Mamluk sultan Kotuz, versed in both steppe and civilized cavalry tactics, fought fire with fire and sucked the pursuing Mongols into an ambush. Once the two sides were engaged, the battle itself was decided by a series of confrontational cavalry charges, with the Mamluks finally scattering their Mongol enemy to the wind.
The ‘western way of war’ acquired new weapons and tactics in the late medieval period. In England, King Edward I faced Welsh light infantry longbowmen while pacifying northern Wales, then incorporated this form of withering missile fire in his wars against the Scots (see the battle of Falkirk, Chapter 5). Edward’s grandson Edward III had similar success against the Scots at Halidon Hill and the French at Crécy, as did Henry V at Agincourt. All of these English monarchs understood the value of showering a ‘killing field’ with arrow shafts to thin out the ranks of opposing heavy cavalry knights before shock combat ensued. Light infantry archers, dealing out death from a distance, added a new brutal dimension to western warfare, presaging the rise of light infantry gunners in the ‘age of gunpowder’.
The medieval western way of war also witnessed a return to classical themes. In the Alps, Swiss militia drilled in a new form of phalanx, resurrecting a lethal form of heavy infantry capable of meeting and beating the finest chivalry in Christendom. Swiss successes at Morgarten, Laupen and Sempach in the fourteenth century illustrate the effectiveness of this new model battle square. Using halberds, pikes and polearms of all sorts, these Swiss heavy infantrymen hacked, bludgeoned and thrust their way to battlefield victory and their cantons’ self-determination using a form of particularly ferocious shock combat where no quarter was given to knight or common warrior, nor expected in return. Their reputation established, Swiss soldiers found employment as both mercenaries and emulators among other national armies, spreading their brand of western war to other regions of Europe.
New martial technologies also had an impact on the development of western-style warfare in the late medieval period, chief among them gunpowder. Though it was invented in China, it was the Europeans who ultimately fully recognized gunpowder’s full potential and set out to produce the first generation of western artillery and handguns. Siege guns helped bring an end to the ‘age of castles’ and centralize the authority of monarchs all over Europe, while light infantry handgunners, armed with matchlocks and arquebuses, challenged medieval crossbowmen and archers for the premier position of distance killer, ushering in a new age of western warfare where missile, not shock combat, was the preferred means of killing.
By the time the Peace of Westphalia in 1648 ended the Thirty Years War a new age of organized violence had dawned. State-sponsored warfare fought with professional armies was becoming the norm in the seventeenth century. Standardization of weapons and tactics, brought on by the success of the Spanish and Dutch tactical systems, changed the lethality and scope of European warfare. For the first time since the fall of Rome, battles were consistently fought between armies of tens of thousands of combatants. And once again, victory was determined by a balanced combined-arms tactical system utilizing cavalry in support of an ascendant infantry, one where the correct application of shock and missile-based technologies by brilliant commanders won the day. In the seventeenth century and beyond, the dual heritage of the ‘western way of war’ and decisive battle would help western civilization reach out and dominate the rest of the globe.