William Lloyd Garrison (December 10, 1805 – May 24, 1879) was a prominent American abolitionist, journalist, suffragist, and social reformer. He is best known as the editor of the abolitionist newspaper The Liberator, which he founded with Isaac Knapp in 1831 and published in Massachusetts until slavery was abolished by Constitutional amendment after the American Civil War. He was one of the founders of the American Anti-Slavery Society, and promoted "immediate emancipation" of slaves in the United States.