Released from the cadet corps as a second lieutenant, in 1749 Volkonsky already bore the rank of colonel. Repeatedly traveled to Poland "for intelligence and secret negotiations with the tycoons". During the Seven Years' War, distinguished himself at Paltzig and Kunersdorf. He was promoted to lieutenant general on August 18, 1759. Two years later he was appointed commander of the troops stationed in Poland. In 1762, he signed an armistice with Prussia in Neumark.