He attended Transylvania University, and then graduated at Yale College in 1832; three years later was elected to the Kentucky General Assembly. He opposed the annexation of Texas yet served in the Mexican-American War.
Read more about Cassius Marcellus Clay, free from Kentucky Educational Television. Unlike Henry Clay, but like one of his inspirations, William Lloyd Garrison, Cassius Clay supported the immediate abolition of slavery, yet was also politically pragmatic, supporting any necessary means, including gradual legal change if it was practical. This led to some later biographers confusing the views of Cassius Clay with those of Henry Clay. Cassius Clay was among the founders of the Republican party, a leader of its antislavery wing, and a friend of Abraham Lincoln, whom he also supported for the presidency.
His colorful and violent career as an outspoken abolitionist in a slave-holding region included owning and publishing the True American, an antislavery newspaper in Lexington, Kentucky (moved to Cincinnati, Ohio after an attack by a racist mob). He survived repeated assassination attempts and beatings by mobs. His life has been chronicled in both his autobiography and in several later biographies.
In 1861, after the outbreak of the Civil War, President Lincoln nominated Clay for the post of ambassador to Spain, but Clay declined the appointment.
Instead, from 1861 to 1862 he was Minister to Russia where he witnessed the Czar's emancipation edict. After being recalled to the United States to accept a commission as Union major general from Lincoln, he publicly refused to accept the commission unless Lincoln would sign an emancipation proclamation. After Lincoln, who did not entirely support emancipation at that time, discussed it with Clay, he sent Clay back to Kentucky to assess the mood for emancipation there and in other border states. Clay returned, reported that it was fine, and Lincoln issued the proclamation a few weeks later.
Clay subsequently returned to Russia, from 1863 to 1869, again as Minister, where he was influential in the negotiations to purchase Alaska. Upon his return he founded the Cuban Charitable Aid Society to help aid the Cuban independence movement of Jose Marti. He also began speaking out against robber barons and in favor of nationalizing the railroads. He left the Republican Party due, in part, to President Grant's military interference in Haiti.
Clay sponsored his friend Rev. John G. Fee's abolitionist ministry in Madison County, Kentucky, and contributed money and land to Fee's founding of the town of Berea and of Berea College.
Clay died July 22, 1903. Survivors included his daughters, the women's rights activists Laura Clay and Mary Barr Clay. His family home, White Hall, is now maintained by the Commonwealth of Kentucky as White Hall State Historic Shrine.
The world-famous professional boxer Muhammad Ali was originally named Cassius Marcellus Clay, Jr. after his father, Cassius Marcellus Clay, Sr., who was named for the emancipationist.