L.Q.C.Lamar was born at the family home of “Fairfield,” in Putman County, Georgia, the son of Lucius Quintus Cincinnatus Lamar and Sarah Williamson Bird. He was a cousin of future associate justice Joseph Lamar, and nephew of Buonaparte Lamar, second president of the Republic of Texas.
He graduated from Emory College, and in 1845, he married the daughter of Augustus Longstreet. In 1849, Lamar’s father-in-law, Professor Longstreet, moved to Oxford, Mississippi, to take the position of chancellor at the recently established University of Mississippi.
Lamar followed him and took a position as a professor of mathematics for a single year. He also practiced law in Oxford, eventually taking up the role of planter, establishing a cotton plantation named Solitude at Abbeville, Mississippi.
In 1856, Lamar was elected to the U.S. House of Representatives. Lamar retired from the House in December 1860 to become a member in the Mississippi Seccession Convention. The Mississippi Ordinance of Secession was drafted by Lamar. Mississippi seceded from the Union and joined the Confederacy on January 9, 1861.
In 1862, Confederate States President Jefferson Davis appointed Lamar as Confederate minister to Russia and special envoy to England and France. When the Civil War was over, he returned to the University of Mississippi where he was a professor of metaphysics, social science and law.
In 1865, 1868, 1875, 1877, and 1881, he was also a member of Mississippi’s constitutional conventions. After having his civil rights restored following the war, Lamar returned to the House in 1873, the first Democrat from Mississippi to sit in the U.S. House of Representatives since the Civil War. He served there until 1877. Lamar would go on to represent Mississippi in the U.S. Senate from 1877 to 1885.
Lamar served as United States Secretary of Interior under President Grover Cleveland from March 6, 1885 to January 10, 1888. President Cleveland appointed Lamar to the United States Supreme Court, and he was confirmed on January 16, 1888, making him the first justice of Southern origin appointed after the Civil War. He served on the court until his death on January 23, 1893.
Lamar is the only Mississippian to have served on the court. Three U. S. counties are named in his honor: Lamar County, Alabama; Lamar County, Georgia; and Lamar County, Mississippi.. Lamar was also featured in John F. Kennedy’s book, Profiles in Courage, both for his eulogy speech for Massachusetts Senator Charles Sumner in 1874. L.Q. C. Lamar is interred at St. Peter’s Cemetery in Oxford, Mississippi.