Robert Carter I (c. 1664 – 4 August 1732) was an American planter, merchant, and colonial administrator who served as the acting governor of Virginia from 1726 to 1727.

An agent for the Northern Neck Proprietary, Carter emerged as the wealthiest settler in the British colony of Virginia and received the sobriquet "King" from his contemporaries connoting his autocratic approach and political influence.

[1] Born around 1664 at Corotoman in Lancaster County, Carter received a classical education and studied the tobacco trade in London.

Carter was appointed agent of the Northern Neck Proprietary in 1702 though lost the lease to his political opponent, Edmund Jenings, in 1711.

[7] Carter inherited one thousand acres (400 ha) in Lancaster County, one-third of his personal estate, and several of his father's theology books.

[2] Carter's father arranged provisions for a formal education and noted his second son should study Latin with guidance from a private tutor.

While in the House of Burgesses, Carter served on two important committees (for Elections and Privileges and for Examination of Propositions and Grievances).

Carter continued to attend Council meetings until the General Assembly adjourned on 1 July 1732, five weeks until his death.

Carter served two terms totaling nearly 20 years, as agent for the Fairfax Proprietary of the Northern Neck of Virginia, essentially the land between the Potomac and Rappahannock rivers westward to the Blue Ridge Mountains.

[13] When Carter became agent for Fairfax's interests again in 1722 (holding that position for a decade, until 1732), in addition to forwarding land rents back to Lord Fairfax, he secured for his children and grandchildren about 110,000 acres (450 km2) in the Northern Neck, as well as additional land in Virginia west of the Blue Ridge Mountains.

Tobacco was the primary cash crop, but the farms also produced beans, corn and wheat, as well as cattle and hogs for domestic consumption.

[14] When Lord Fairfax saw Carter's obituary in the London monthly The Gentleman's Magazine, he was astonished to read of the immense personal wealth acquired by his resident land agent.

Charles Carter (1707–1764) would exchange the land he had inherited for other property and built Cleve Hall in King George County, which he represented for many years in the House of Burgesses.