On May 23, 1618, two Catholic councillors sent by Vienna to meet with Bohemian nobles were thrown out from the upper floors of the Prague castle, triggering the Bohemian Revolt against Habsburg absolutism, which snowballed into the wider European conflict, known as the Thirty Years’ War.
Since the Bohemian Reformation of the second half of the 14th century and the subsequent Hussite Wars, during which the followers of Jan Hus defeated five consecutive crusades proclaimed against them by the Pope, the Bohemian estates of the predominantly Catholic Holy Roman Empire had remained almost entirely Protestant and enjoyed varying degrees of religious and political freedom.
The Peace of Augsburg
The Peace of Augsburg of 1555 seemingly settled religious disputes within the Holy Roman Empire, by allowing rulers to choose either Lutheranism or Catholicism as the official confession of their state. But the compromise failed to resolve underlying religious and political tensions within the Empire. Notably, the settlement did not recognize any of the Reformed traditions, such as Calvinism and Anabaptism.
As a result, growing tensions between Protestant and Catholic rulers gradually undermined the Peace of Augsburg, and when the Imperial Diet opened in February 1608, the Protestants demanded formal confirmation of the Augsburg settlement, which was especially significant for Calvinist Prince-electors like Frederick IV of Palatine.
But when the Habsburg Archduke Ferdinand ruled that the renewal of the Peace of Augsburg should be conditional upon the restoration of all church land appropriated since 1552, Frederick IV formed a coalition of Protestant states, known as the Protestant Union. In response, the Catholic Maximilian of Bavaria set up the Catholic League, a military alliance “for the defence of the Catholic religion and peace within the Empire”.
The Second Defenestration of Prague
In 1617, as his health deteriorated, Emperor Matthias sought to assure an orderly transition during his lifetime by naming his cousin, the fiercely Catholic Ferdinand of Styria, as his successor. A staunch proponent of the Counter-Reformation, the Jesuit-educated Ferdinand saw Protestantism as harmful to the Empire and aimed to impose absolutist rule on Bohemia while encouraging conversion to the Catholic faith.
His election as Crown Prince led to deep consternation among many Bohemian Protestants, who feared not only the loss of their swindled properties, but also of their traditional semi-autonomy, which had ensured religious freedom throughout Bohemia.
In May 1618, the King-elect sent two Catholic councillors to Prague Castle to meet with disgruntled Bohemian nobles who wanted to air their grievances. But the two imperial representatives and their secretary were seized and thrown out of the castle windows.
Known as the Second Defenestration of Prague, the event triggered what came to be known as the Bohemian Revolt, which quickly spread through the lands of the Bohemian Crown, before expanding into Silesia and the Habsburg heartlands of Lower and Upper Austria.
The Bohemian Revolt
The Protestant estates and Catholic Habsburgs immediately started gathering allies for war. When Ferdinand II was elected Holy Roman Emperor after the death of Matthias in 1619, the Bohemian estates deposed him as King of Bohemia and replaced him with leading Calvinist Frederick V of Palatine, the son of Frederick IV, and son-in-law of the Protestant King James VI and I, of Scotland, England and Ireland.
By June 1620, Ferdinand II, now fully established as Emperor, set out to conquer Bohemia and make an example of the rebels. Imperial forces under the leadership of Field Marshal Tilly pacified Lower Austria while the army of the Catholic League pacified Upper Austria before the two armies united and moved north into Bohemia.
After conquering most of western Bohemia, the Imperial army made for Prague. Under the command of Prince Christian of Anhalt, the Bohemian army managed to get ahead of the Imperial army and set up defensive positions at Bílá Hora (“White Mountain”) near the Bohemian capital.
But the Bohemian army was no match for Emperor Ferdinand’s troops. The Battle of White Mountain lasted only an hour and left the Bohemian army in tatters, with some 4,000 Protestants killed or captured, while Imperial losses amounted to only about 700.
The Thirty Years’ War and Counter-Reformation
With the Bohemian army destroyed, Tilly entered Prague, King Frederick fled the country, the Bohemian Revolt collapsed, and Europe was engulfed in the Thirty Years’ War, still considered today as one of the most destructive conflicts in European history,
Forty-seven leaders of the Bohemian insurrection were put on trial, and twenty-seven of them were executed in Prague’s Old Town Square. Twelve of their heads were impaled on iron hooks and hung from the Old Town Bridge Tower. The Emperor then ordered all Calvinists and other non-Lutherans to leave the realm in three days or to convert to Catholicism, and by 1627, most Bohemians had converted.
The defeat at the Battle of White Mountain thus brought two centuries of re-Catholicization of the Czech lands and the decline of the Czech-speaking aristocracy. It also ensured that the Bohemian lands would remain in Habsburg hands for nearly three hundred years.
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