Battle of White Mountain (8 November 1620)

In 1609, Emperor Rudolf II had granted a Letter of Majesty, ensuring religious freedom for Protestants throughout Bohemia. This act had been inherited by his successor Matthias I, but, as he became gravely ill in 1617, some Bohemian noblemen felt that the freedoms were encroached by his named successor, Ferdinand, an outspoken leader of the Counter-Reformation. In May 1618, a group of Bohemian noblemen met with representatives of the Emperor to discuss their grievances; as the discussion became heated, the former threw the imperial delegates out of a window, in what became known as the Second Defenestration of Prague. This was a key event that is considered to have led to the Thirty Years War.

In early 1619, Ferdinand became Emperor of the Holy Roman Empire and King of Bohemia. In response, the revolting Bohemian nobles chose the Calvinist Elector Palatine Frederick V as King of Bohemia in November 1619. Ferdinand II responded by attacking Bohemia with the support of the Catholic League. The armies met at the White Mountain (Bílá Hora) near Prague. An army of 15,000 Bohemians and mercenaries led by Christian of Anhalt was defeated by 27,000 men of the combined armies of Ferdinand II, Holy Roman Emperor led by Charles Bonaventure de Longueval, Count of Bucquoy and the German Catholic League under Johann Tserclaes, Count of Tilly. Subsequently, Ferdinand entered Prague and ousted Frederick, who fled to the Netherlands. 

Ferdinand ordered a massive effort to bring about re-conversion to Catholicism in Bohemia and Austria, causing Protestantism there to nearly disappear in the following decades, and reducing the Bohemian Diet's power.

Credit: Georgiana Hedesan (June 2018)