The Battle of Byczyna, also known as the Battle of Pitschen, was the deciding battle of the 1587–1588 War of the Polish Succession, which erupted after two rival candidates were elected to the Polish throne. The two opposing sides had forces nearly evenly matched, with armies about 6,000 strong, roughly half infantry and half cavalry. The battle was an overwhelming victory for the Polish-Swedish faction, led by the Swedish-born king-elect Sigismund III Vasa, over the army of his rival to the throne, Maximilian III, Archduke of Austria.