The Thirty Years’ War was a series of European conflicts lasting from 1618 to 1648, involving most of the countries of Western Europe, and fought mainly in Germany. The struggle’s direction and character were decisively influenced by various issues, including the dynastic rivalries of ambitious German princes and the determination of certain European powers, notably Sweden and France, to curb the power of the Holy Roman Empire, which was the chief political instrument of Austria and the ruling Habsburg family. Of the many rivalries at stake, perhaps the most notable was between the Hohenzollern in north-central Europe and the Habsburg in central Europe.
This war was one of the first to be accompanied by a significant propaganda effort. The royal houses on both sides of the conflict needed to generate passionate support in their subjects, and the political ambitions of leaders were not sufficient to motivate support for large-scale military action. Religion would be the center of the propaganda effort. Instead of the leadership’s desire for more land, power, and money (the real reasons), the people would be told that they were fighting a Reformation war: Protestant vs. Catholic. The success of this deception depended upon the ordinary person’s lack of information about the other countries involved in the war.
The religious differences that were used as an excuse for the Thirty Years’ War had existed for more than half a century before 1618. In large measure, this situation had resulted from the Peace of Augsburg, an agreement concluded in 1555 between the Holy Roman Emperor and the Lutheran princes of Germany. The generation of nobles who signed this agreement were serious Lutherans and Catholics, and – although they were convinced of the incorrectness of the other’s religious views – knew that their common heritage required that they acknowledge each other as serious, if erring, Christians, and were therefore willing to sign a peace treaty intended to yield a peaceful co-existence.
By 1618, a different generation of nobles was in power. Although nominally either Catholic or Lutheran, they had in fact no serious Christian faith, and were therefore willing to wage war for personal gain. But they were also willing to use religion as an excuse for war, and so they pointed to the religious differences, which had caused no conflict for 63 years, as suddenly somehow necessitating a war.
The war, which was one of the most destructive conflicts in European history, may be divided into four phases, usually styled and dated as follows: Palatine-Bohemian (1618-25), Danish (1625-29), Swedish (1630-35), and French (1635-48).
Tensions were seriously aggravated in Germany prior to the war. Seeking to extend imperial control into the internal affairs of the various German kingdoms, the emperor, who was Catholic, pointed to the fact that many of the kingdoms were Lutheran: Protestant churches in many parts of Germany were destroyed by imperial troops, restrictions were placed on the rights of Protestants to worship freely, and the emperor’s officials made the Treaty of Augsburg the basis for a general resurgence of Roman Catholic power. The emperor also tried to control the internal affairs of the Catholic German kingdoms, but in those cases, of course, he could not use religious differences as an excuse. The German kings were eager to protect their rights to govern their own territories, and to prevent the emperor’s meddling. The emperor, in turn, found allies who would help him try to gain control of the internal affairs of the German kingdoms. With the establishment (1608) of the Evangelical Union, a Protestant defensive alliance of princes and cities, and of the Catholic League (1609), the organization of those who would support the emperor, a violent solution to the crisis became inevitable. The Bohemian section of the Evangelical Union struck the first blow. Outraged by the aggressive policies of the imperial hierarchy in Bohemia, the Bohemians demanded that Ferdinand II, then king of Bohemia, intervene. The king, an ardent Roman Catholic and the Habsburg heir presumptive, ignored the appeal; the majority of Bohemia’s population was Lutheran, and religion made a convenient excuse: in reality, the emperor was concerned about his ability to exercise autonomous power. The peaceful co-existence of a Roman Catholic minority within Bohemia further weakened the emperor’s argument that his reaction to the Bohemians was founded on differences in faith. In 1618, citizens of Prague invaded the royal palace, seized two of the king’s ministers, and threw them out a window. This act, known as the Defenestration of Prague, was the beginning of a national uprising.
The Bohemian forces achieved numerous initial successes, and the rebellion swiftly spread to other parts of the Habsburg dominions. For a brief period in 1619 even Vienna, the Habsburg capital, was threatened by Evangelical Union armies. Later in 1619 the Bohemians bestowed the crown of the deposed Ferdinand on Frederick V, elector of the Palatinate. Several sections of the Evangelical Union, which consisted chiefly of Lutherans, thereupon withdrew from the struggle, because Frederick was a Calvinist. Taking advantage of Protestant dissensions - particularly a declaration of war against Bohemia by Lutheran Saxony, and a Spanish invasion of the Upper, or Bavarian, Palatinate - Ferdinand, who had become Holy Roman emperor in August 1619, quickly assumed the offensive. In 1620, a Catholic League army, commanded by the German soldier Tilly, routed the Bohemians at Weisserberg (White Mountain), near Prague. Bloody reprisals were inflicted on the Bohemians after this victory, and Protestantism was outlawed. Although the Evangelical Union disintegrated, Frederick and a few allies continued the struggle in the Palatinate. The Protestants defeated Tilly’s army in 1622 but thereafter met with successive disasters. By the end of 1624 the Palatinate, which was awarded to Maximilian I, duke of Bavaria, had been forcibly returned to the Roman Catholic fold. Frederick’s brother-in-law was a Hohenzollern, who remained neutral during the early years of the conflict; the result was that Brandenburg was ravished by mercenaries and looters from both sides.
The second phase of the war assumed international proportions when various German states sought foreign assistance against resurgent imperialism. England, France, and other western European powers were alarmed at the increasing might of the Habsburgs, but France and England, then allies against Spain, refrained from immediate intervention in the war because of domestic difficulties. The Roman Catholic and Lutheran populations were also becoming aware of the fact that this war was motivated by political ambition, and that their respective faiths – far from calling for war – required them to work for peace. The Christian writers of this era expressed their abhorrence of war and the materialism that causes it and thrives in it; they stressed the pacifistic aspect of Christian thought which makes the preservation of human life an imperative. The king of Denmark and Norway, Christian IV, however, came to the aid of the German states. Christian IV’s intervention was substantially motivated by national considerations, mainly territorial ambitions in northwestern Europe and a determination to end Habsburg control of the Danish duchy of Holstein, Germany.
Supported by German princes, Christian IV mobilized a large army in the spring of 1625 and invaded Saxony (Sachsen). The expedition encountered little effective resistance until a year later. In the meantime, the famous military leader Albrecht von Wallenstein had created a powerful army of mercenaries and entered the service of Ferdinand II, whose only other available force was that of the Catholic League under Tilly.
The use of mercenaries was another blow to the attempt to paint this war as religious: the mercenaries were notorious for their lack of any faith or morals. They often would switch sides in the conflict, seeking a better wage. Wallenstein’s mercenaries won their first victory in April 1626. In August 1626, Tilly completely defeated the main body of Christian IV’s army at Lutter am Barenberge, Germany. The combined imperial armies subsequently overran all of northern Germany, leaving numerous pillaged towns and villages in their wake. Wallenstein’s mercenaries were motivated only by the desire for wealth and adventure, and cared for neither Roman Catholic nor Protestant sensibilities. The destruction they brought upon the communities which they entered was massive, including rape, murder, torture, killing of livestock, and the burning of houses and grain fields. With Wallenstein in pursuit, Christian IV retreated in 1627. Total victory for the imperial cause was signaled when Ferdinand issued the Edict of Restitution. This document nullified Protestant titles to all Roman Catholic property expropriated since the Peace of Augsburg. This meant a massive increase of territory for the empire. In 1629, King Christian IV accepted the Treaty of Lübeck, which deprived him of numerous small holdings in Germany.
Ferdinand’s successes in the second phase of the war sharpened the anti-Habsburg orientation of the French Richelieu, chief minister of King Louis XIII. Because of recurring internal crises, Richelieu was unable to intervene directly in Germany, but he made overtures to Gustav II Adolph of Sweden. A Lutheran, Gustav had already received appeals from the hard-pressed North Germans. Because of this circumstance, as well as the promise of French support and Swedish ambitions for hegemony in the Baltic region, Gustav entered the conflict. In the summer of 1630 he landed a well-trained army on the coast of Pomerania. The rulers of Pomerania, Brandenburg, and Saxony - including the royal family of the Hohenzollern - vacillated on whether to participate in the Swedish venture, seriously delaying the start of the campaign. While Gustav marked time, Tilly, who had been given command of Wallenstein’s army, laid siege to Magdeburg, Germany, which was then in a state of insurrection against the empire. The imperial armies captured and sacked the city in 1631, and massacred the inhabitants. Much of the city was destroyed by fires that spread during the fighting and pillaging. The violence against the citizenry again violated both Roman Catholic and Protestant sensibilities; it was becoming clear that the savageness of this war was in no way motivated by any faith, but rather by the desire - on the part of the princes - for land and power, and the desire - on the part of the mercenaries - for money and adventure.
Tilly was repulsed by the Swedes on three occasions in the following summer. George-Wilhelm of Brandenburg, a Hohenzollern, was now supporting Gustav II Adolph with men and money, if not enthusiastically. In the last of these battles, fought at Breitenfeld, Germany (now Leipzig), Gustav was supported by the Saxon army. The Saxons broke ranks and fled at the first charge, exposing Gustav’s left flank and nearly costing him the battle; but he regrouped his forces and routed Tilly’s troops, about 6000 of whom were killed or captured. After the Battle of Breitenfeld the Swedish army moved into southern Germany for the winter. The spring campaign brought numerous victories, notably the defeat (1632) of Tilly, who was mortally wounded on the banks of the Lech River, and the capture of Munich, Germany. Faced with complete disaster, Ferdinand had meanwhile recalled Wallenstein to command the imperial war effort. Wallenstein, hurriedly recruiting a new army of mercenaries, invaded Saxony in the fall of 1632. The Swedish army followed and attacked the imperial force, then entrenched at Lützen, Germany. The ensuing battle cost Gustav his life, but at the end Wallenstein’s army was forced to withdraw. Bernhard, duke of Saxe-Weimar, who succeeded to Gustav’s command, overran Bavaria after this victory, but during 1633 Wallenstein struck repeated blows against the Swedish strongholds in Silesia. Toward the close of 1633 Wallenstein initiated a peace movement among leading circles of the imperial armies. Removed from his command by Ferdinand on suspicion of treason, Wallenstein then entered into peace negotiations with the Protestant leaders. His attempts to end the War aroused the enmity of his own officers, and in 1634, he was assassinated. The imperial armies inflicted a devastating defeat on Duke Bernhard at Nördlingen, Germany. Dismayed by this catastrophe, the leaders of the Protestant coalition swiftly abandoned the struggle. The Peace of Prague (1635), which formally ended the third phase of the war, provided for certain concessions to the Saxons, particularly basic modifications of the Edict of Restitution. Thus the German states regained some of the territory that the emperor had attempted to claim.
The Swedish phase of the war, thus concluded, confirmed that the conflict was not a religious one, because the Lutherans Swedes had happily made common cause with the Roman Catholic French.
In its final phase, the war became an imperialist conflict for hegemony in Western Europe between the Habsburgs and France, which was still under the leadership of Richelieu. Religious issues, which had never been the cause of the conflict, were not significant in the final phase, which opened in May 1635, with France declaring war against Spain, the chief Habsburg dominion aside from Austria. France, which was allied with Sweden and various German Protestant leaders, including Duke Bernhard, was able to quickly overcome serious difficulties that developed during the first stage of the fighting. Thus Roman Catholic France declared war on Roman Catholic Spain, and on the Roman Catholic Habsburg Empire, and allied itself with Lutheran Sweden and the Lutheran parts of Germany. It was now clear that this was not a religious war. The Swedish general defeated a combined force of Saxons and Austrians in 1636, materially damaging the Habsburg position in Germany. In 1636, Spanish invasions of French territory were repelled. The Habsburg position in Germany was further damaged by a defeat inflicted by Duke Bernhard in 1638. After these setbacks the imperial armies were forced to surrender their European strongholds one after another. Between 1642 and 1645 the Swedish scored numerous triumphs, overrunning Denmark, which had become allied with the empire, and ravaging large sections of western Germany and Austria. In the west, the French were also generally successful. Condé routed a Spanish army in France, in 1643. During the following November the French suffered a severe defeat in Germany, but thereafter the Habsburgs were not successful in the war, except in some minor battles.
The French armies badly mauled a Bavarian army in 1644. Representatives of the empire and the anti-Habsburg coalition began peace discussions at Münster and at Osnabrück in 1645, but the negotiations, primarily a concession to the war-weary peoples of western Europe, remained fruitless for a protracted period. After central Bavaria was invaded, however, Maximilian I of Bavaria concluded, in 1647, the Truce of Ulm, with Sweden and France.
Despite these and other reverses, Emperor Ferdinand III refused to capitulate. Desultory fighting continued in Germany, Luxembourg, the Low Countries, Italy, and Spain throughout the remainder of 1647. In the fall of 1647 Maximilian I re-entered the war on the side of the empire. Another army of Bavarians and Austrians was defeated in May 1648. This defeat, as well as the siege of Prague, the siege of Munich, and an important French victory at Lens, France, forced Ferdinand, also confronted with the threat of an assault on Vienna, to agree to the peace conditions of the victors.
The Peace of Westphalia, signed in 1648, fundamentally influenced the subsequent history of Europe. The Hohenzollern family gained dynastic importance. In addition to establishing Switzerland and the Dutch Republic as independent states, the treaty gravely weakened the empire and the Habsburgs, ensured the emergence of France as the chief power on the Continent, and disastrously slowed the political unification of Germany.
The economic, social, and cultural consequences of the war were vast, with Germany the principal victim. Modern estimates suggest that the total population of Germany fell by at least 25 percent; some regions suffered a loss of over 55 percent as a result of casualties and the displacement of their residents. Villages, as opposed to fortified towns, suffered the most. Except in port cities such as Hamburg and Bremen, economic activity went into decline all across Germany. Uncertainty, fear, disruption, and brutality marked everyday life and remained a memory in German consciousness for centuries.