William Lloyd Garrison is one of the best-known abolitionists, and published the widely read antislavery journal, The Liberator.
As a young publisher, Garrison quickly caused trouble in New York by denouncing a northern shipper active in the international slave trade. Garrison was jailed for libel and was not released until Arthur Tappan, a New York businessman and abolitionist, paid his fine.
In 1830 Garrison settled in Boston, where on January 1, 1831 he began publishing his antislavery newspaper. This was this first publication in the country to call for immediate abolition.
Garrison did not expect that slavery could be ended "immediately," but he and his New England AntiSlavery Society argued that moral people should act and talk as though it should be.
Read more about William Lloyd Garrison at the link below.