Kościuszko was born in February 1746, in a manor house on the Mereczowszczyzna estate in Brest Litovsk Voivodeship, then Grand Duchy of Lithuania, a part of the Polish–Lithuanian Commonwealth. At age 20, he graduated from the Corps of Cadets in Warsaw, Poland. After the start of the civil war in 1768, Kościuszko moved to France in 1769 to study. He returned to the Commonwealth in 1774, two years after the First Partition, and was a tutor in Józef Sylwester Sosnowski's household. In 1776, Kościuszko moved to North America, where he took part in the American Revolutionary War as a colonel in the Continental Army. An accomplished military architect, he designed and oversaw the construction of state-of-the-art fortifications, including those at West Point, New York. In 1783, in recognition of his services, the Continental Congress promoted him to brigadier general.