The war started on May 23, 1618, when a crowd of Protestants stormed the royal castle in Prague and threw two members of the Catholic government (men who were appointed by the Habsburgs) and their secretary out the window. This incident became known as the Defenestration of Prague and was the official beginning of the Thirty Years' War. Even though none of them died, having landed in a pile of manure, this incident started a chain reaction of events that railed almost the whole of Europe for 30 years.
In 1617 Ferdinand II is crowned King of Bohemia, but in 1619 the Protestants crown Fredrick V to counteract Ferdinand’s counter-reformations. Ferdinand trades his hereditary lands and his status as an imperial elector to Maximilian I for enough forces so put a stop to Fredrick in the battle of White Mountain with General Johann Tserclaes von Tilly leading his forces. Later that day, Fredrick and his English wife, Princess Elizabeth, flee the country and become known as the Winter king and Queen. Later their Grandson becomes the King of Great Britain, George I.
With Ferdinand in full control 36,000 Protestant families flee the country letting him sell all their land for a profit. Albrecht von Wallenstein becomes governor of the Kingdom of Bohemia thanks to Ferdinand and with special permissions for currency is able to buy 60 estates that makes him lord of the whole of northeastern Bohemia. He then gives Ferdinand a way out of dealing with Maximilian by raising an army on his own. For this Ferdinand makes Wallenstein chief of all the imperial forces.
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