Prince Józef Zajączek (Coat of arms of Świnka), (1 November 1752, Kamieniec Podolski — 28 August 1826, Warsaw) was a Polish general and politician. Zajączek started his career in the Army of the Polish-Lithuanian Commonwealth, an aide-de-camp to hetman Franciszek Ksawery Branicki. He was Branicki's supporter on the political scene, before joining the liberal opposition during the Great Sejm in 1790. He became a radical supporter of the Constitution of 3 May 1791. As a military commander, in the rank of a general, he participated in Polish–Russian War of 1792 and Kościuszko Uprising. After the partitions of Poland, he joined the Napoleonic Army, and was a general in Napoleon's forces until his wounding and capture during Napoleon's invasion of Russia in 1812. From 1815 he became involved in