Thirty Years’ War (1618-1648) was a series of religious and political conflicts that eventually involved most European nations. The conflict began as a revolt against religious policies instituted by Austrian Habsburg rulers of the Holy Roman Empire that promoted Roman Catholicism. It soon spread across Germany. It eventually became a general struggle over territory and the balance of power between France and the Habsburg rulers in Austria and Spain.
Causes of the war.
The underlying cause of the war was the longstanding hostility and fear between Protestants and Catholics within the massive Holy Roman Empire. The empire stretched across central Europe. It included what are now Austria, Belgium, the Czech Republic, Germany, northern Italy, the Netherlands, western Poland, and Switzerland. The Protestants and Catholics disagreed in their interpretation of the Peace of Augsburg (1555), which had temporarily ended earlier religious warfare in Germany. The peace agreement did not allow for the spread of Protestantism in formerly Catholic bishoprics (lands governed by a bishop). It had recognized Catholics and Lutherans, but not Calvinists and other Protestants, whose numbers had grown in southern and central Germany. These groups also demanded recognition. By mid-1609, the fear of renewed conflict led to the formation of two armed associations—the Protestant Union and Catholic League.
The Bohemian period
(1618-1624). A conflict over constitutional liberties between Protestants in Bohemia (now part of the Czech Republic) and their Roman Catholic rulers led to the war. The spark came from a policy sponsored by Ferdinand, the recently elected Habsburg king of Bohemia, that reduced the number of Protestant churches. When Protestant leaders appealed to Emperor Matthias, he ignored their petition. A group of Protestants took action in May 1618 by throwing three of the emperor’s officials out a window in what became known as the Defenestration of Prague. At first, most of Germany’s Protestant princes stayed on the sidelines.
In 1619, the Bohemian Protestants removed Ferdinand from the throne and replaced him with a Calvinist ruler, Frederick V of the Palatinate, an area in central Germany. Meanwhile, Matthias died. Germany’s princes elected Ferdinand as Holy Roman emperor. Ferdinand took the title Ferdinand II. He enlisted the help of the Catholic League and Spain’s king, who was a member of the Spanish branch of the Habsburg family. In 1620, the League’s general, Johan Tserclaes, Count Tilly, decisively defeated the Bohemians in the Battle of the White Mountain. Bohemia was soon reconquered. The Protestant ringleaders were executed. Ferdinand made Catholicism the sole religion in Bohemia.
The Danish period
(1625-1629). With Ferdinand restored in Bohemia and the Palatinate occupied by a Spanish army, the other Protestant countries began to feel threatened. The Lutheran king of Denmark, Christian IV, resumed the struggle in northern Germany. The emperor’s general Albrecht von Wallenstein raised a huge army of about 130,000 soldiers and adventurers.
Wallenstein’s army and Tilly’s Catholic League forces soundly defeated the Danish king, who signed the Treaty of Lübeck in 1629. Meanwhile, Emperor Ferdinand had issued the Edict of Restitution. It provided that all church possessions that the Protestants had acquired since 1552 be returned to Catholic control. The edict marked the height of the emperor’s power. However, it led other leaders in the empire to oppose him, because Ferdinand had issued the edict without consulting them. Even Ferdinand’s supporters felt threatened by Wallenstein’s power and convinced the emperor to dismiss the ambitious general.
The Swedish period
(1630-1634). Ferdinand’s triumph alarmed Germany’s neighbors. Although the king of France was Catholic, his chief minister, Cardinal Richelieu, was eager to defeat the Habsburgs. France encouraged the ambitious Swedish king, Gustavus Adolphus, to continue to war. In 1630, Gustavus Adolphus set sail from Sweden with more than 13,000 men to relieve the northern German city of Magdeburg, which Tilly was besieging. The Swedish king had the best-trained and best-disciplined army in Europe, but he arrived too late to prevent the capture, looting, and destruction of the city. The presence of the Swedish army and Protestant outrage at the violence persuaded the powerful northern Protestant states of Brandenburg and Saxony to join Gustavus. In 1631, the Swedish army defeated Tilly in the Battle of Breitenfeld. Afterward, the Swedish forces won another important battle, and Tilly was killed in the fighting.
Emperor Ferdinand recalled Wallenstein, who quickly gathered another large army. Philip IV of Spain also sent troops to help his Austrian Habsburg cousin. Wallenstein’s army met the Swedish forces in the Battle of Lützen (1632). The Swedes won, but Gustavus Adolphus was killed in the battle.
The Swedes continued the struggle until 1634, when they were badly beaten by a combined Spanish and Austrian army in the Battle of Nördlingen. When Wallenstein began negotiating with the Protestants, Ferdinand secretly authorized the general’s assassination. One year later, the victorious Ferdinand acted to end the war by signing a compromise Peace of Prague with most of the German princes.
The Swedish-French period
(1635-1648). Cardinal Richelieu now convinced France’s King Louis XIII to deprive the Habsburgs of victory and peace by intervening on the Protestant side. The war lost most of its religious character as Catholic France joined forces with the Protestant German princes, the Dutch Republic, and Sweden. The war became a struggle for power in Europe, pitting the royal Bourbon family of France and its allies against the Austrian and Spanish Habsburgs. In 1635, the French army invaded Germany, where it joined the Swedish army in winning a series of victories. Ferdinand’s successor, Ferdinand III, was forced to desert his Spanish allies and accept less favorable peace terms from his enemies.
The Peace of Westphalia
(1648). Negotiations began in 1644 between the emperor and the German princes, France, Sweden, and the Dutch Republic. Spain was excluded. The diplomats met separately in two different cities of Westphalia, in what is now western Germany. The tough negotiations dragged on until the Peace of Westphalia was signed in 1648. France acquired most of Alsace. The Dutch Republic and Swiss Confederation became independent of the German empire. Sweden got control of the mouths of the Oder, Elbe, and Weser rivers. Calvinism acquired equal footing with Catholicism and Lutheranism in the empire. The emperor’s constitutional power was greatly reduced.
Results of the war.
Thirty years of war devastated most of Germany. Many people died from violence, disease, and starvation. Whole cities, villages, and farms were destroyed or disappeared. It took more than 100 years for Germany’s economy and population to recover.
