He took part in the Russo-Polish War of 1792. After the outbreak of Kościuszko's Uprising of 1794, Wawrzecki founded and financed a number of military units to fight in the regions of Samogitia and Courland. At the same time he was also a plenipotentiary of the Supreme National Council, the de facto government of Poland. On 16 October 1794, he was promoted by Kościuszko to the rank of Lieutenant General. Following Kościuszko's defeat in the battle of Maciejowice, the Council (on insistence of Hugo Kołłątaj) nominated Wawrzecki as Kościuszko's successor as the commander in chief of the uprising. After the Battle of Praga he withdrew with the remnants of his forces to Radoszyce, where he disbanded his troops and surrendered himself to the Russians.