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The Thirty Years' War

At the height of its power, the Holy Roman Empire, ruled by the Austrian Habsburgs, and its ally Spain, ruled by the Spanish members of the Habsburg family, dominated European politics. A number of developments in the sixteenth and seventeenth centuries, however, made life more difficult for Europe’s most powerful family.

First, the Holy Roman Empire could only rule effectively when it had the cooperation of those local and provincial officials the emperor put in power. As the empire’s power peaked, though, many princes simply waited for the opportunity to break with it.

Second, nations such as France and Sweden were waiting for the chance to take shots at the empire—and take land. Finally, the Reformation (see Chapters 3 and 4) drove a wedge between the electors within the empire, some Lutheran and some Catholic. The Peace of Augsburg of 1555 was to help maintain a balance between the two religious groups. In the years prior to the war, though, a few of the electors had converted to Calvinism, a religious denomination not legalized at Augsburg. Religious tensions in Germany built as some of the German princes chose Calvinism. What started arguably as a German civil war between Ferdinand and Prince Frederick of the Palatinate soon escalated into an international war of politics and religion that manifested itself in four distinct phases.

Out the Window

The Protestants in Bohemia took great exception to the appointment of Ferdinand II as King of Bohemia, and later as Holy Roman Emperor. Ferdinand reneged on the tolerance shown to Protestants by his predecessors including Holy Roman Emperor Rudolf. Catholic authorities stopped the construction of a number of Protestant houses of worship. The Protestant nobility of Bohemia was on the verge of a revolt. At the castle in Prague, a number of prominent Protestants seized two Catholic officials along with their trusty secretary and flung the three from a window high in the castle. Remembered as the Defenestration of Prague of 1618, this event helped spark the Thirty Years’ War.

Define Your Terms

The term defenestration comes from the Latin meaning “out the window." The 1618 defenestration, although considered the defenestration, actually was the second significant event of its kind. The first involved followers of Jan Hus.

The Protestant and Catholic accounts of the defenestration vary greatly. In reality, the three Catholics not only survived the fall but also escaped with only their pride damaged. They landed in a ditch beneath the window filled with a trash heap, most probably piles of manure, that helped break their fall. According to the three men (and thus the official Catholic version), they called out to Jesus and Mary on their way down and angels swooped down from the heavens, caught the righteous men, and sat them gently on the ground unharmed—with no piles of manure involved.

The Bohemian Phase (1618-1625)

Occasionally historians subdivide the Bohemian Phase into two smaller phases, the Bohemian Phase (1618-1621) and the Palatinate Phase (1621-1624 or 1625). The first of the fighting erupted in Bohemia in 1618 at least partly as a result of the defenestration. Archduke Ferdinand, of the House of Habsburg, of course, became king of Bohemia in 1617. Wanting to exercise his power and defend his faith, King Ferdinand took away some of the religious liberties the Bohemians had enjoyed for generations. The Protestants organized a resistance movement comprised mostly of Czechs against Ferdinand and his oppressive Catholicism and deposed him. In his place, they chose Frederick V of the Palatinate, a Calvinist.

Define Your Terms

The Palatinate was an area of Germany along the Rhine River which prior to 1356 was ruled by a count palatine, originally a permanent representative of the king of the Franks, and after 1356 by an elector, one of the princes who elected the Holy Roman Emperor.

Imperial forces of the recently elected Holy Roman Emperor Ferdinand II quickly descended upon the resistance; the Catholic League and the Spanish Habsburgs subsidized the expense of building a military. The combat came to a screeching halt when imperial forces crushed the Protestants near Prague at the Battle of White Mountain. The emperor then used Jesuit missionaries to work over the noncombatants. Rather than giving up, as the imperial forces hoped, the Protestants’ will for self-determination only increased. Despite the increased efforts of the Protestants, the imperial forces prevailed and Bohemia eventually lost its Protestant identity.

As the first phase of the war unfolded, private mercenary armies formed hoping to cash in on the fighting. Among the more dynamic and ambitious leaders of these mercenary armies was Albrecht von Wallenstein (1583-1634). Although Wallenstein was born a Czech Protestant, he offered his services to the emperor; after all, he was a mercenary. After much pressure from those around him, the emperor gave in and commissioned Wallenstein and his army of 125,000 men. Wallenstein and his troops had their way with Germany; they pillaged and plundered at will. Because Wallenstein built his army, his troops were loyal only to him and not to the emperor. Though Wallenstein rose to power during the Bohemian Phase of the war, he would leave his indelible mark during the second phase.

The Spanish seized the opportunity to successfully invade Frederick’s holdings along the Rhine River while Frederick was busy in Bohemia. After the invasion, Frederick, with the aid of other Protestants, tried to free his lands from the Spanish. Despite their best efforts, the Protestants failed to wrest them from the Spanish.

The Danish Phase (1625-1630)

Enemies of the Habsburgs from around Europe, Protestants and Catholics alike, watched in terror as the imperial forces, led by Wallenstein, razed the Protestant resistance in Germany. In an effort to end the imperial push through Germany and aid fellow Protestants, the King of Denmark, Christian IV (1577-1648), invaded northern Germany. While Christian certainly invaded as the champion of the antiHabsburg cause, he had every intention of exerting his influence on the region in the process. Onlookers from as far away as the Netherlands and England cheered Christian, but to no avail. Out-manned, he fell to Wallenstein as had so many other challengers in places like Silesia, Schleswig, and the Baltic region.

Encouraged by Wallenstein, the emperor issued the Edict of Restitution in 1629. The edict outlawed Calvinism and other sects of Christianity and allowed only Catholicism and Lutheranism in the empire. The Peace of Augsburg, 70 years earlier, had allowed Lutherans to keep all lands confiscated from the Church during the Reformation. The Edict of Restitution required that all lands previously confiscated from the Church by Protestantism be returned.

This marked the pinnacle of Habsburg power in Europe. Protestants across the continent now feared both Wallenstein and the emperor: Wallenstein because of his armies and ruthless tactics, and Ferdinand because he seemed close to unifying and giving the Holy Roman Empire actual power. Concerned that Wallenstein had grown too strong and no longer represented their interests, the leaders of the provinces within the empire and the Catholic League pressured the emperor to relieve Wallenstein of his duties.

The Swedish Phase (1630-1635)

While religion remained the ostensible reason for the continued fighting, politics emerged as the real reason for the war during the Swedish Phase. Since the first champion of Protestantism had failed to thwart the Habsburgs, Europe desperately needed another. The Swedes had been busy in northern Europe grabbing land for trade purposes for some time when the Protestant King of Sweden, Gustavus Adolphus (1594-1632) announced his plan to enter the fight against the Habsburgs.

While his 100,000-man army had the potential to seriously damage the imperial forces, Gustavus Adolphus also hoped to expand his holdings in his foray into Germany. Subsidized by France, the Swedes won major victories that probably prevented Ferdinand from uniting all German states under the control of the Holy Roman Empire. While it might seem strange for France, a Catholic nation, to support the Protestant Swedes against fellow Catholics, France saw an opportunity to weaken the Habsburgs and to tip the balance of power away from them. With a confident and successful Gustavus Adolphus in the north, the emperor found himself in the unenviable position of inviting Wallenstein to rejoin the cause.

The French Phase (1635-1648)

Unfortunately for the Swedes and the Protestants, Gustavus Adolphus died from a battle wound in 1632. Then the Swedes were, for the most part, defeated in 1634. In an unsurprising turn of events, Wallenstein turned on Ferdinand, in anger over his first dismissal and with hopes of creating a kingdom of his own. Ferdinand declared Wallenstein guilty of treason and had him murdered by his own troops. As the tides turned against the Protestant princes, some of the princes offered peace in exchange for the rejection of the Edict of Restitution. The timing couldn’t have been better, and Ferdinand welcomed the prodigal sons back into the fold as allies.

Continental Quotes

“The Lord God is my armor!"

— Gustavus Adolphus, spoken before his final battle in which he refused to wear armor because of a wound he received in the previous battle.

With the Swedes no longer able to do France’s dirty work, France officially entered the war on the side of the Protestants days before news of the peace between the empire and some of the princes went public. Just as France supported the United Provinces against the Spanish Habsburgs, France supported the Protestants against the Habsburgs.

The weaker the Habsburg family, particularly in neighboring Spain, and the Holy Roman Empire, the greater France’s status was in European political affairs.

Would You Believe?

Because the French Phase of the Thirty Years' War involved Germans, French, Dutch, Scots, Swedes, Spanish, and even Finns, historians often refer to it as the International Phase.

Because neither the empire nor the Protestants could deliver the knockout punch, the fighting dragged on and on. There were virtually no decisive battles in the final phase of the war.

Would You Believe?

The French and Spanish did not wrap up their fighting with each other until the Treaty of the Pyrenees in 1659.

Casualties mounted on the battlefields with no victors, and civilians away from the battlefields suffered heavy casualties, too. The non-Germans who rushed to the aid of the Protestants in Germany burned and looted every place they went in Germany in an attempt to weaken their opponents. In the long run, this tactic proved devastating for all Germans. As was typical of seventeenth-century warfare, the armies and the weapons were larger and more deadly than ever before in European history. However, war tended to drag on as each side bludgeoned the other without ever delivering the final blow. Finally, after 30 years of long, drawn-out fighting, the two sides started winding down in 1643. With all involved exhausted, the Thirty Years’ War officially ended in 1648 with the Peace of Westphalia, one of the most significant settlements in all of European history.

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