Siege of Pilsen

Battle context

The Siege of Pilsen, lasting from 19 September to 21 November 1618, was the first significant military action of the Thirty Years' War. Following the Bohemian Revolt — the proximate cause of the broader conflict — a Bohemian army under Ernst von Mansfeld captured Plzeň from a substantially smaller Habsburg garrison. The disparity in recorded force sizes, 20,000 Bohemian troops against 4,000 Habsburg defenders, underscores the weight brought to bear on the city. Habsburg casualties of 2,500 against Bohemian losses of 1,100 reflect the cost of the defense. As the opening operational episode of a war that would consume Central Europe for three decades, the fall of Plzeň established early Bohemian momentum in the revolt against Habsburg authority and marked the transition from the political crisis of the Defenestration of Prague into open armed conflict.