He successfully fought in Lithuanian Livonia against Sweden from 1600s to 1617. He took part in the campaign against the Swedes in the Baltic region in 1621–1622 (Polish-Swedish War), where he agreed to a controversial truce (as he had no permission to negotiate it from the king or the Sejm). Important commander of Lithuanian forces during the Smolensk War, where he was instrumental in obtaining the capitulation of the Russian army in the relief of Smolensk. Afterwards, in 1635, he retired from his military career, concentrating on administering his estates. A Calvinist, he was a great protector of Protestants in Lithuania.