Who was involved in a controversial debate over slavery in the Senate, escalating tensions in the 1850s?

The correct answer is Charles Sumner, who was a prominent figure in the Senate known for his staunch opposition to slavery. In 1856, he delivered a powerful speech titled "The Crime Against Kansas," which criticized pro-slavery forces and their actions in Kansas, a region embroiled in violent conflict known as "Bleeding Kansas." Sumner's speech was inflammatory and drew the ire of many pro-slavery senators.

The tensions escalated significantly when, shortly after his speech, Sumner was physically attacked by Congressman Preston Brooks, who brutally assaulted him in retaliation for the speech. This incident epitomized the deep divisions in American society over the issue of slavery during the 1850s and highlighted the fact that political debate had devolved into violence. Sumner's role in this event made him a martyr for the anti-slavery cause and significantly heightened sectional tensions between the North and South leading up to the Civil War.

Others involved in the broader debates over slavery, such as Henry Clay, Stephen Douglas, and James Buchanan, played significant roles in discussions and legislation related to the issue, including the Compromise of 1850 and the Kansas-Nebraska Act. However, it was Sumner's direct confrontation and subsequent beatdown