Osterman, Andrei Ivanovich, Count (əndrāˈ ēväˈnəvĭch əstyĭrmänˈ) [key], 1686–1747, Russian statesman, b. Germany. His original name was Heinrich Johann Friedrich Ostermann. Under Czar Peter I he held various positions in the diplomatic service. He was made baron for his role in negotiating the Treaty of Nystad, which ended (1721) the Russo-Swedish Northern War. Under Czarina Catherine I, Osterman directed Russian foreign policy and was a member of the privy council. A master court intriguer, he was able to maintain his powerful position under the three rulers who followed Catherine. He shrewdly sided with Czarina Anna upon her accession in 1730 against the privy council's attempt to limit her powers. He negotiated an end to the War of the Polish Succession (1733–35) and the Russo-Turkish War of 1736–39. During the brief regency of Anna Leopoldovna, Osterman was the virtual ruler of Russia. After Elizabeth seized (1741) power, Osterman was sentenced to death but then was reprieved and exiled to Siberia.