two Catholic representatives, Vilem Slavata and 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. Thurn established a Protestant-dominated government in Bohemia, while unrest expanded into Silesia and the Habsburg heartlands of 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. Spanish involvement inevitably drew in the Dutch, and potentially France, although the strongly Catholic Louis XIII of France faced his own 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 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. By mid-June 1619, the Bohemian army under Thurn was outside Vienna and although Mansfeld's defeat by Imperial forces at Sablat forced him to return to Prague, Ferdinand's position continued to worsen. 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 1620 Polish war, followed by the 1623 to 1639 conflict with Persia. On 19 August, the Bohemian Estates rescinded Ferdinand's 1617 election as king; on the 26th, they formally offered the crown to Frederick.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. With the exception of Christian of Anhalt, Frederick's advisors urged him to reject it, as did the Dutch, the Duke of Savoy, and his father-in-law James I of England. 17th century Europe was a highly structured and socially conservative society, and their lack of enthusiasm was due to the implications of removing a legally