The oldest son of an obscure Yorkshire gentleman, George Calvert used ability and an Oxford education to gain wealth, status, and influence in the England of his time. Knighted in 1617, and a member of Parliament for Yorkshire in 1621, Calvert served as one of James I's two secretaries of state and a Privy Councilor from 1619 to 1625.
As a recent convert to Catholicism, Calvert resigned from his government posts in the latter year, when anti-catholic legislation was being debated in Parliament. Created Baron Baltimore of Baltimore in 1625, with large estates in County Longford, Ireland, Calvert devoted the next seven years of his life to colonization projects in America.
Having sponsored a small colony at Ferryland in his Province of Avalon, Newfoundland, as early as 1620, Lord Baltimore visited his American possessions in 1627 and 1629, and by the latter date, was determined to obtain lands in a friendlier climate. His petition for a large colonial grant with unprecedented powers, located north of the Potomac River, was agreed to by Charles I, but Calvert died almost two months to the day before the charter for Maryland was officially granted (on 20 June 1632).