Editing Thirty Years' War (section)

===Bohemian Revolt===
{{Main|Bohemian Revolt}}
[[File:Friedrich V. von der Pfalz bis.jpg|thumb|left|upright=1.0|"Winter's King", [[Frederick V of the Palatinate]], whose acceptance of the Bohemian Crown sparked the conflict]]

Ferdinand once claimed he would rather see his lands destroyed than tolerate [[heresy]] within them. Less than 18 months after taking control of [[Duchy of Styria|Styria]] in 1595, he had eliminated Protestantism in what had been a stronghold of the [[Reformation]].{{Sfn|Bassett|2015|p=14}} Absorbed by their war in the Netherlands, his Spanish relatives preferred to avoid antagonising Protestants elsewhere. They recognised the dangers associated with Ferdinand's fervent Catholicism, but supported his claim due to the lack of alternatives.{{Sfn|Wedgwood|1938|pp=74–75}}

On being elected king of Bohemia in May 1617, Ferdinand reconfirmed [[Letter of Majesty|Protestant religious freedoms]], but his record in Styria led to the suspicion he was only awaiting a chance to overturn them. These concerns were heightened after a series of legal disputes over property were all decided in favour of the Catholic Church. In May 1618, Protestant nobles led by [[Jindřich Matyáš Thurn|Count Thurn]] met in [[Prague Castle]] with Ferdinand's two Catholic representatives, [[Vilem Slavata of Chlum|Vilem Slavata]] and [[Jaroslav Borzita of Martinice|Jaroslav Borzita]]. In what became known as the [[Third Defenestration of Prague]], both men were thrown out of the castle windows along with their secretary [[Filip Fabricius]], although all three survived.{{Sfn|Wedgwood|1938|pp=78–79}}

Thurn established a Protestant-dominated government in Bohemia, while unrest expanded into [[Silesia]] and the Habsburg heartlands of [[Lower Austria|Lower]] and [[Upper Austria]], where much of the nobility was also Protestant. Losing control of these threatened the entire Habsburg state, while Bohemia was one of the most prosperous areas of the Empire and its electoral vote crucial to ensuring Ferdinand succeeded Matthias as Emperor. The combination meant their recapture was vital for the Austrian Habsburgs but chronic financial weakness left them dependent on Maximilian and Spain for the resources needed to achieve this.{{Sfn|Bassett|2015|pp=12, 15}}

Spanish involvement inevitably drew in the Dutch, and potentially [[Kingdom of France|France]], although the strongly Catholic [[Louis XIII of France]] faced his own [[Huguenot rebellions|Protestant rebels]] at home and refused to support them elsewhere. The revolt also provided opportunities for external opponents of the Habsburgs, including the Ottoman Empire and [[Savoyard state|Savoy]]. Funded by Frederick and [[Charles Emmanuel I, Duke of Savoy]], a mercenary army under [[Ernst von Mansfeld]] was sent to support the Bohemian rebels. Attempts by Maximilian and John George of Saxony to broker a negotiated solution ended when Matthias died in March 1619, since many believed the loss of his authority and influence had fatally damaged the Habsburgs.{{Sfn|Wedgwood|1938|pp=81–82}}

By mid-June 1619, the Bohemian army under Thurn was outside [[Vienna]] and although Mansfeld's defeat by imperial forces at [[Battle of Sablat|Sablat]] forced him to return to Prague, Ferdinand's position continued to worsen.{{Sfn|Wedgwood|1938|p=94}} [[Gabriel Bethlen]], Calvinist [[Prince of Transylvania]], invaded Hungary with Ottoman support, although the Habsburgs persuaded them to avoid direct involvement; this was helped when the Ottomans became involved in the [[Polish–Ottoman War (1620–21)|1620 Polish war]], followed by [[Ottoman–Safavid War (1623–1639)|the 1623 to 1639 conflict with Persia]].{{Sfn|Baramova|2014|pp=121–122}}

On 19 August, the Bohemian Estates rescinded Ferdinand's 1617 election as king; on the 26th, they formally offered the crown to Frederick. Two days later, Ferdinand was elected emperor, making war inevitable if Frederick accepted the Bohemian Crown. Most of Frederick's advisors urged him to reject it, as did the Duke of Savoy, and his father-in-law James I.{{Sfn|Wedgwood|1938|pp=98–99}} The exceptions included [[Christian I, Prince of Anhalt-Bernburg|Christian of Anhalt]] and [[Maurice, Prince of Orange|Maurice of Orange]], for whom conflict in Germany was a means to divert Spanish resources from the Netherlands. The Dutch offered subsidies to Frederick and the Protestant Union, helped raise loans for Bohemia, and provided weapons and munitions.{{sfn|Israel|1995b|p=469}}

[[File:Guerre 30 ans 1.jpg|right|thumb|upright=1.1|The Catholic counter-offensive; [[Count of Tilly|Tilly]]'s campaign during the Bohemian revolt and Palatine campaign]]

However, wider European support failed to materialise, largely due to lack of enthusiasm for removing a legally elected ruler, regardless of religion.{{Sfn|Wedgwood|1938|pp=98–99}} Although Frederick accepted the crown and entered Prague in October 1619, his support eroded over the next few months. In July 1620, the Protestant Union proclaimed its neutrality, while John George of Saxony backed Ferdinand in return for the cession of [[Lusatia]], and a guarantee of Lutheran rights in Bohemia. Maximilian of Bavaria funded a combined Imperial-Catholic League army led by [[Johann Tserclaes, Count of Tilly|Count Tilly]] and [[Charles Bonaventure de Longueval, 2nd Count of Bucquoy|Charles of Bucquoy]], which pacified Upper and Lower Austria and occupied western Bohemia before marching on Prague. Defeated by Tilly at the [[Battle of White Mountain]] in November 1620, the Bohemian army disintegrated, and Frederick was forced to flee the country.{{Sfn|Wedgwood|1938|pp=127–129}}