Sussex County, with an area of 515 square miles, was formed in 1753 from Surry and was named for an English county. Cornwallis passed through the county in 1781. Greensville County, with an area of 307 square miles, was formed in 1780 from Brunswick and was probably named for Sir Richard Grenville, leader of the settlement on Roanoke Island in 1585. Cornwallis passed through that county in 1781.