Benjamin Harrison IV (1693 – July 12, 1745) was an American Virginia planter, politician, and Member of the Virginia House of Burgesses. He was the son of Benjamin Harrison III, and the father of Benjamin Harrison V, who was a signer of the Declaration of Independence and the fifth Governor of Virginia. Harrison is also known as the builder of Berkeley which is believed to be the oldest three-story brick mansion in Virginia and is the ancestral home to two Presidents of the United States: William Henry Harrison, his grandson, and Benjamin Harrison his great-great-grandson. Two powerful and influential families in colonial Virginia, the Harrison family and the Carter family, were united when Harrison married Anne Carter, the daughter of Robert "King" Carter. His family also forged ties to the Randolph family as four of his children married four grandchildren of William Randolph I.
Benjamin Harrison IV was born in a small house on the plantation named "Berkeley Hundred" or "Berkeley Plantation". Upon completion of his studies at The College of William & Mary, he became the Harrison family's first college graduate. Harrison settled on his family estate and, like his predecessors, he increased his land holdings. Around 1722, Harrison married Anne Carter, whom William Byrd II had described as "a very agreeable girl". As part of a dowry from Robert Carter, Harrison managed and received profits from land that was technically owned by his father-in-law. This land was entailed by Carter to Harrison's son, Carter Henry Harrison. Using bricks fired on the Berkeley plantation, Harrison built a Georgian-style three-story brick mansion on a hill overlooking the James River in 1726. Berkeley would later earn a distinction shared only with Peacefield in Quincy, Massachusetts as the ancestral home for two United States Presidents. In 1729, Harrison purchased 200 acres of the Bradford plantation from Richard Bradford III. From 1736 to 1742, he represented Charles City County, Virginia in the House of Burgesses.