Charles Sumner CDV Sumner was a U.S. senator and leader of the antislavery forces in Massachusetts sought to free all slaves. In 1856, a South Carolina Congressman, Democrat Preston Brooks, nearly killed Sumner on the Senate floor two days after Sumner delivered an intensely anti-slavery speech called "The Crime Against Kansas". In the speech, Sumner characterized the attacker's cousin, South Carolina Senator Andrew Butler, a Democrat, as a pimp for slavery. No Back mark.