Ignacy Czesław Łempicki was a major in the infantry regiment in 1766. He was elected a member of the 1767 Sejm as a representative of the Zakroczym Land. Russian minister plenipotentiary Nikolai Vasilyeich Repnin, in an attachment to the message to the President of the Foreign Affairs College of the Russian Empire Nikita Ivanovich Panin of October 2, 1767, described Łempicki as the MP responsible for the implementation of Russian plans at the 1767 Sejm for which the king is responsible.