Thirty Years’ War

The Thirty Years’ War, the major European military conflict of the seventeenth century, was a struggle that began as a religious conflict but ended as a confrontation waged for secular political reasons. By its close, the political power of the Holy Roman Empire was weakened severely and France emerged as the predominant power in Europe.

Summary of Event

In the sixteenth century, the rise of Lutheranism and Calvinism led to numerous wars and conflicts among the advocates of the new reformed churches and those who defended Catholicism. In 1555, the Peace of Augsburg recognized Lutheranism and established the principle of cuius regio, eius religio, literally, “whose rule, his the religion.” In other words, the religion of a prince or political leader determined the religion that was to be practiced within a given realm. The Peace of Augsburg, however, failed to legitimize Calvinism; that factor, and the emergence of a dedicated Counter-Reformation (also known as the Catholic Reformation) Counter-Reformation[CounterReformation] , led to the Thirty Years’ War. [kw]Thirty Years’ War (1618-1648)
[kw]War, Thirty Years’ (1618-1648)
Wars, uprisings, and civil unrest;1618-1648: Thirty Years’ War[0760]
Diplomacy and international relations;1618-1648: Thirty Years’ War[0760]
Religion and theology;1618-1648: Thirty Years’ War[0760]
Europe;1618-1648: Thirty Years’ War[0760]
Bohemia;1618-1648: Thirty Years’ War[0760]
Denmark;1618-1648: Thirty Years’ War[0760]
France;1618-1648: Thirty Years’ War[0760]
Germany;1618-1648: Thirty Years’ War[0760]
Sweden;1618-1648: Thirty Years’ War[0760]
Thirty Years’ War (1618-1648)

Another reason for continued conflict has to do with the way the Peace of Augsburg was applied within the religiously and ethnically diverse Holy Roman Empire. During the reign of Emperor Rudolf II Rudolf II (Holy Roman Emperor) , the Catholic Habsburgs sought to impose their religious views on those under their control, but regional and local Protestant leaders resisted these efforts. Decades of mutual mistrust and antagonism crystallized with the formation of the Evangelical (Protestant) Union Evangelical Union in 1608 and the Catholic League Catholic League the following year. The immediate cause of the outbreak of the war in 1618 was the closing of Protestant churches in Bohemia by representatives of Holy Roman Emperor Matthias Matthias (Holy Roman Emperor) . Subsequently, the emperor’s representatives in Prague were thrown out of a palace window, in an action known as the Defenestration of Prague Defenestration of Prague (1618) . Protestantism;Europe

The Bohemian Phase (1618-1625). The initial phase of the war, the Bohemian Phase (1618-1625), was marked by the repudiation of Emperor Matthias’s authority. The Evangelical Union sprang into action to denounce the emperor’s closing of Protestant churches. In the initial skirmishes and battles, the Protestants scored one victory after another. In early 1619, the Evangelical Union approached Vienna and threatened to lay siege to the Habsburg capital, but they had an inadequate force. In that same year, Protestant leaders named Elector Frederick V Frederick V of the Palatinate, son-in-law of King James I of England, as the king of Bohemia; the Catholic claimant was the new Holy Roman Emperor, Ferdinand II Ferdinand II (Holy Roman Emperor) , who had replaced Matthias upon his death. Ferdinand II capitalized upon growing dissent with the Protestant camp and took the offensive that resulted in the Habsburg victory at the Battle of White Mountain White Mountain, Battle of (1620) (Weisserberg) on November 8, 1620. The Protestants were devastated by this defeat, but they regrouped in the spring of 1622 to win the Battle of Wiesloch, Weisloch, Battle of (1622) their only major victory in this phase of the war. After Wiesloch in April, 1622, the imperial Habsburg forces prevailed; the Evangelical Union was dissolved and the Palatinate and Bohemia were returned to the control of the emperor.

The Danish Phase (1625-1629). Christian IV, Christian IV (king of Denmark and Norway) king of Denmark and Norway, emerged as the leader of the Protestant cause in 1625, marking the start of the Danish phase of the war. Christian knew that he would benefit from eliminating Habsburg control in northern Germany. From the very outset of this phase of the war, however, it was evident that Christian had made a strategic mistake that would be compounded by a series of tactical errors. Habsburg imperial armies under Albrecht Wenzel von Wallenstein Wallenstein, Albrecht Wenzel von and Count Johan Tserclaes Tilly Tilly, Count Johan Tserclaes von defeated the Protestant forces in the Battles of Dessau Bridge (April 25, 1626) Dessau Bridge, Battle of (1626) and Lutter (August, 1626) Lutter, Battle of (1626) . Habsburg victories were followed by the Edict of Restitution Restitution, Edict of (1629) on March 6, 1629, an imperial decree that specified that all land seized from Catholics since the Peace of Augsburg was to be returned to the Catholic family from which it had been seized, and that only the Catholic and Lutheran religions were acceptable—all others were subject to persecution. Catholicism;Europe

During 1629-1630, Wallenstein conducted a violent persecution Persecution, religious;Calvinists of Calvinist and other dissenters. The Danish phase of the war came to an end with the Peace of Lübeck (May 22, 1629) Lübeck, Peace of (1629) . In that agreement between Ferdinand II and Christian IV, the Danish king received almost all of his lands back in return for a pledge to remove himself from German political and religious affairs.

The Swedish Phase (1630-1635). In the summer of 1630, the war was resumed when King Gustavus II Adolphus Gustavus II Adolphus of Sweden arrived with an army to champion the Protestant cause. Gustavus refused to accept the Treaty of Lübeck and wanted to acquire territory in Pomerania and other north German coastal areas to secure his previously won acquisitions in Finland and the Baltic Sea. In 1631, Tilly defeated German forces and seized Magdeburg (May 20, 1631) Magdeburg, Battle of (1631) , but the imperial army was defeated by Gustavus’s Swedes, supported by a Saxon force, at the Battle of Breitenfeld Breitenfeld, Battle of (1631) on September 17, 1631. In 1632, Tilly died in the failed defense of Munich; the Swedes and their allies were in Bavaria. Gustavus was killed during the Battle of Lützen (November 16, 1632) Lützen, Battle of (1632) .

Axel Oxenstierna, Oxenstierna, Axel the Swedish chancellor, assumed command of the Swedish army and continued the offensive, receiving the military assistance of Bernard Bernhard , duke of Saxe-Weimar. While the offensive continued, Oxenstierna, a diplomat, recognized the vulnerability of the Swedish position near the Danube River, so he initiated contact with the French chief minister Cardinal de Richelieu, Richelieu, Cardinal de which resulted eventually in transforming this original religious war to a modern political struggle. Wallenstein, who had alienated many of his officers and troops through his Catholic radicalism, was assassinated on February 25, 1634. Later that year, the imperial armies under Prince Ferdinand Ferdinand III (Holy Roman Emperor) (later Ferdinand III) scored a major victory over the Swedish-German army at the Battle of Nördlingen (September 6, 1634) Nördlingen, Battle of (1634) . By that time, both sides were exhausted and the populace (both Catholic and Protestant) clamored for peace. The subsequent Peace of Prague (May 30, 1635) Prague, Peace of (1635) curtailed the implementation of the Edict of Restitution (1629) and returned some lands to Protestant leaders.

The French-Swedish Phase (1635-1648). Even before the Peace of Prague was signed, the fourth and final phase of the Thirty Years’ War began. Unlike the initial three phases, the French-Swedish phase—sometimes called simply the French phase—commenced outside the German realm. Cardinal de Richelieu, chief minister to King Louis XIII Louis XIII of France, attacked Spain in May, 1635. Spain had been held by the Habsburgs, and Richelieu believed that French security required the defeat and containment of the Habsburgs Habsburgs;Spain
Spain;Habsburgs . Catholic France went to war with the Catholic Habsburgs—in Spain and in Central Europe. The tenor of the final phase of the war was set in 1636, when Spanish military efforts were repelled by French forces, and at Rheinfelden (March 2, 1638) Rheinfelden, Battle of (1638) , when the Habsburgs were defeated by a Swedish-German coalition.

During the French-Swedish phase, there was some realignment of allies. Christian IV of Denmark became an ally of the Habsburgs and was defeated during a two-year Swedish-Danish War (1643-1645) Swedish-Danish War (1643-1645)[Swedish Danish War (1643-1645)] . Despite occasional setbacks, such as the defeat at Tuttlingen Tuttlingen, Battle of (1643) on November 24-25, 1643, French forces were ultimately successful. The Swedes won a decisive victory at the Second Battle of Breitenfeld (November 2, 1642) Breitenfeld, Second Battle of (1642) . The Habsburgs lost their Bavarian ally when it entered a separate peace(Truce of Ulm Ulm, Truce of (1647) ) with France and Sweden on March 14, 1647, but within six months Bavaria had reentered the war. Ferdinand III continued the war until the Habsburgs were defeated at Zusmarshausen Zusmarshausen, Battle of (1648) on May 17, 1648, and at Lens Lens, Battle of (1648) on August 20, 1648. During September and October, Emperor Ferdinand III moved toward accepting the terms of the peace treaty that had been developed.

The Peace of Westphalia (1648).
Westphalia, Peace of (1648) Negotiations to bring the Thirty Years’ War to a close were protracted and difficult. While numerous states and principalities were involved, the principal negotiators were France and Sweden on one hand and the Holy Roman Empire and its ally Spain on the other. Initial discussions began in 1644 in Münster and Osnabrück, both in Westphalia, and were continued intermittently until October 24, 1648, when the Peace of Westphalia was signed. The specific terms of the peace included the following:

•France received almost all of Alsace and much of Lorraine and several small towns on the Rhine.

•France and Sweden received the right to vote in the Diet (assembly) of the Holy Roman Empire.

•Sweden gained control of the Baltic Sea and a foothold in Germany by gaining Western Pomerania and Baltic islands; the Swedes also gained control over the Bremen and Verden.

•The United Provinces of the Netherlands and the Swiss Confederation were recognized as independent states.

•Brandenburg received compensation for the loss of Western Pomerania through the acquisition of several towns.

•The operational terms of the Peace of Augsburg were reaffirmed and extended—the religion of the prince determined the religion to be practiced by the people and Calvinism was made an acceptable form of Christianity.

While the Holy Roman Empire remained as an institution until its dissolution by Napoleon Bonaparte in 1806, it was no longer a meaningful factor in European affairs after the Peace of Westphalia was signed in 1648.


The Thirty Years’ War was a defining moment in the history of early modern Europe. In the sixteenth century, the Protestant Reformation of Martin Luther, John Calvin, and other reformers, as well as advancing nationalism, transformed the organization of Europe radically. The medieval unifying concept of Christendom was replaced by competing religious views that were frequently identified with dynastic or national interests.

The reformers opposed one another and all of them were targeted by the Catholic Counter-Reformation that took shape with the Council of Trent (1545-1564) and with the establishment of new religious orders, such as the Jesuits. At the outbreak of the Thirty Years’ War with the Bohemian phase in 1618, the conflict was based on religion, and the contenders’ motivation and actions were delineated on religious lines. Those same factors clearly were primary in the second, Danish, phase. However, during the Swedish phase in the 1630’, the alignment of forces began to be predicated on dynastic or national priorities rather than religion. Catholic France joined Protestant Sweden against the Catholic Holy Roman Empire. After 1648, no major European war would be fought primarily over religious differences.

The impact of the Thirty Years’ War was substantial, for it altered the geopolitical orientation of European affairs. France would be the predominant power for more than two centuries and Central Europe witnessed a struggle between the Habsburgs of Austria and the Hohenzollerns of Prussia, a struggle that resulted in the establishment of the Prussian dominated German Empire in 1871. Also, the independence of the Netherlands and Switzerland were recognized at the Peace of Westphalia.

In human terms, the war was devastating. Estimates of the direct and indirect casualties of the war run as high as eight million. The Thirty Years’ War is also significant because of a growth of secularism in Europe; while religion and churches continued to have meaning for Europeans after 1648, the influences of Christian values and institutions declined.

The war paralleled another significant movement—the scientific and intellectual revolution of the seventeenth century—where the thought of Francis Bacon, René Descartes, Johannes Kepler, Isaac Newton, Thomas Hobbes, and John Locke presented a new worldview that was founded upon an extension of human values and a hope for a new society that would be based upon reason and not religion or spirituality alone.

Further Reading

  • Asch, Ronald G. The Thirty Years’ War: The Holy Roman Empire and Europe, 1618-48. New York: St. Martin’s Press, 1997. Asch argues that the essential points of contention in the Thirty Years’ War were religion and the constitutional crisis in the German world—the battle over sovereignty between the Habsburgs and the northern German princes. A solid introduction to the war.
  • Benecke, Gerhard, ed. Germany in the Thirty Years’ War. New York: St. Martin’s Press, 1979. A relatively brief but valuable study of Germany’s role in the Thirty Years’ War from the Peace of Augsburg in 1555 through the late 1640’. Includes both narrative and excerpts of primary sources on politics and the constitution, economics and the military system, religion and propaganda, and sections on the war’s social impact.
  • Bireley, Robert. The Jesuits and the Thirty Years’ War: Kings, Court, and Confessors. New York: Cambridge University Press, 2003. A valuable study by a Jesuit on the focus among the Catholic and increasingly nationalist dynasties in Madrid, Paris, Vienna, and Munich. The text is based on a wealth of primary sources and is geared toward the reader with some historical familiarity with the war.
  • Guthrie, William P. Battles of the Thirty Years’ War: From White Mountain to Nordlingen, 1618-1635. Westport, Conn.: Greenwood Press, 2002. The best and most comprehensive account of the military actions during the Bohemian, Danish, and Swedish phases of the Thirty Years’ War. Guthrie’s excellent appendices provide valuable information on many aspects of the battles.
  • Guthrie, William P.. The Later Thirty Years’ War: From the Battle of Wittstock to the Treaty of Westphalia. Westport, Conn.: Greenwood Press, 2003. Guthrie’s account of the French phase of the Thirty Years’ War is the best and the most detailed account in English. Provides excellent, detailed appendices.
  • Lockhart, Paul D. Denmark in the Thirty Years’ War, 1618-1648: King Christian IV and the Decline of the Oldenburg State. Selinsgrove, Pa.: Susquehanna University Press, 1996. A well-written and well-researched account of Christian IV’s lamentable misunderstanding of Denmark’s strategic position and military capabilities and his miscalculated intervention in the name of national and dynastic defense. Lockhart is at his best when examining the impact of the conflict on the Danish political system and the subsequent success of absolute monarchy over the shared governance of the king with the aristocracy.
  • Maland, David. Europe at War, 1600-1650. Totowa, N.J.: Rowman and Littlefield, 1980. An excellent survey of the causes, outbreak, development, and consequences of the Thirty Years’ War. An ideal introductory study for the general reader and student, which combines an understanding of the historical forces that were at play with the most significant facts associated with the struggle.
  • Osborne, Toby. Dynasty and Diplomacy in the Court of Savoy: Political Culture and the Thirty Years’ War. New York: Cambridge University Press, 2002. This is the only study in English of the role of Savoy in the Thirty Years’ War. The work is centered on the role of diplomacy, the aims of the House of Savoy, and the interests of the elite during the war.
  • Parker, Geoffrey. The Thirty Years’ War. New York: Routledge and Kegan Paul, 1987. An excellent introduction to the war, well-written, fully documented, and supported by valuable maps. Parker’s study is one of the best general histories of the conflict.
  • Polisensk , Josef V., and Frederick Snider. War and Society in Europe, 1618-1648. New York: Cambridge University Press, 1978. This excellent study examines the contemporary and later historical sources on the Thirty Years’ War, the problems associated with studying the conflict, and the effects of the war.
  • Ringmar, Erik. Identity, Interest, and Action: A Cultural Explanation of Sweden’s Intervention in the Thirty Years’ War. New York: Cambridge University Press, 1996. A seminal study that argues that Sweden’s entrance into the war in 1630 was based on reasons of identity rather than a rational choice based on dynastic and national interests. Ringmar’s interpretation suggests new approaches for the study of the war.

Related Articles in <i>Great Lives from History: The Seventeenth Century</i><br />

The Great Condé; Ferdinand II; Frederick V; Gustavus II Adolphus; James I; Jules Mazarin; Samuel von Pufendorf; Cardinal de Richelieu; Lennart Torstenson; Viscount de Turenne; Albrecht Wenzel von Wallenstein. Thirty Years’ War (1618-1648)