Born on February 11, 1902 in the Center Hill Section of Orangeburg County, L. Marion Gressette was the son of John Thomas and Rosa Emily Wannamaker Gressette. He was the fourth of eight children. He was educated at the St. Matthews schools and the University of South Carolina, where he graduated in 1924 with an LL.B. degree. He received Honorary Doctor of Law degrees from the University of South Carolina in 1977, from Clemson in 1980 and from The Citadel in 1981.
On August 18, 1927, he married Florence Howell and they became the parents of one son, Lawrence Marion Gressette, Jr.
Admitted to practice in 1924, his honors in the field of law include election as a Fellow of the American College of Trial Lawyers. He was elected to the South Carolina House of Representatives in 1924, and served as a S.C. Senator from 1936 until 1984. He was President Pro Tempore from 1972 to 1984 and chairman of the Senate Judiciary Committee from 1953 to 1984.
He was honored by his colleagues through the hanging of his portrait in the Senate Chamber in 1975 and the dedication of a Senate Office Building in 1979. The Senator from Calhoun can best be described by the following words found in the entrance to the Gressette Senate Office Building:
An individual of unquestioned honor and integrity — a leader with the courage to stand for his convictions — an energetic and persuasive statesman and orator. Blessed by a gracious God and the love and devotion of his wife and family, the Senator from Calhoun devoted a lifetime to the service of the people of South Carolina. As a member of the Senate, he strove untiringly for the advancement of a progressive state without sacrificing its traditional values.