Thomas Cornwallis sailed with Leonard Calvert from England to Maryland, not Virginia, as one of the original Commissioners of the colony.

However, the English civil war between Parliament and Charles I, left the possession of the Maryland Province in question.

He resented that his land had been included in the grant to Lord Baltimore and refused to submit to Maryland's Authority.

In 1635, Cornwallis fought the Virginian colonist William Claiborne and his allies over the jurisdiction of Kent Island,[6] and captured it in 1638.

In 1644[citation needed], Richard Ingle sailed into Chesapeake Bay with his ship, Reformation, and fired on St. Mary's City.