Middleton's father was a carpenter, and his mother was in one of the first graduating classes of what is now South Carolina State University. Middleton himself graduated from Clafin College, Orangeburg's predominantly black Methodist school, where his studies of sociology became the basis of his knack for understanding and communicating with different communities.
A veteran of World War II, Middleton was trained as a Tuskegee Airman in 1942 and then served as an infantry soldier in the Pacific theater. Returning to Orangeburg in 1946, he became a barber and then a restaurant owner before finding his true vocation as a real-estate and insurance salesman. What is now one of the largest and most profitable real-estate firms in Orangeburg began as a sideline in the back of a barbershop, but Middleton quickly developed a reputation for superior knowledge and service. His commitment to inclusive definitions of community gave him opportunities to succeed.
But his success did not come without adversity. As a civil rights activist in the turbulent 1950s and 1960s, Middleton witnessed firsthand the bravery and tragedy of Orangeburg's citizens. Following family tradition, he was a leader in South Carolina's Republican Party, but along with many black Republicans, he switched to the Democratic Party in 1960. He participated in sit-ins and signed a petition to send his daughter to an all-white school. His wife, then the head of South Carolina State's library science department, was jailed for joining a student protest. From these experiences Middleton developed an unconquerable forbearance that complemented his unshakable belief in equality. In 1974 he was among the first wave of twentieth-century African Americans to be elected to the South Carolina General Assembly, where he served for a decade. There he was a founding member of the Legislative Black Caucus and an influential voice on the U.S. Civil Rights Commission.
In partnership with his son, Middleton maintained an active hand in the daily operations of the real-estate business he founded. The agency continues to expand with racially diverse agents serving equally diverse populations.
