(kärl gŭs´täv rān´shöld)
, 16511722, Swedish field marshal. One of the ablest lieutenants of Charles XII in the Northern War, he played an important part in the Polish campaign of 17013 and defeated (1706) the combined Russian, Polish, and Saxon forces at Fraustadt, SW of Poznan. He accompanied Charles on his Ukrainian campaign. When Charles was incapacitated by a wound just before the battle of Poltava (1709), he appointed Rehnskiöld commander in chief. The battle was disastrous for the hopelessly outnumbered Swedes; Rehnskiöld himself was captured by the Russians.