The youngest of the 13 American colonies that declared their independence from Britain in 1776, it was first explored by De Soto in 1540. It was part of the land granted to the lords proprietors of Carolina in the 1660s, receiving a provincial charter in 1719 and attaining status as an independent colony in 1731. At that time, James Oglethorpe arranged for Georgia to receive debtors and persecuted Protestants from England. To these were soon added German Protestants and other refugees. During the war between England and Spain in 1739, Oglethorpe organized an invasion of Florida, which was unsuccessful. Georgia was an early center of support for independence from Britain. In 1778, a British fleet anchored in the Savannah River and sent ashore troops who defeated the American forces. The state remained under British control until 1782. As the state began to become settled, conflicts with the Creek and Cherokee Indians arose. The problem was resolved when, after defeating Indians in battle, the United States resettled them to Oklahoma and took their land. Georgia seceded from the Union in January 1861. General Sherman's famous "March to the Sea" passed through central Georgia in 1864. Jefferson Davis, president of the Confederacy, was captured at Irwinville, Georgia, on May 10, 1865. Georgia was readmitted to the Union in 1870. The state adopted Prohibition in 1908, long before it became a national policy, and retained it until 1938. Georgia was a center of resistance to civil rights. In the early 1940s, the governor of Georgia tried to take over the state university to combat doctrines advocating equality between blacks and whites. Lester Maddox became governor in 1967 on the basis of his reputation as an opponent of equality for blacks.