Although two House members intervened to end the assault, Sumner, who had ripped his desk loose from the bolts holding it to the floor in his effort to escape, was rendered unconscious. He regained consciousness shortly after the attack, but it would be three years before he felt able to resume his senatorial duties.
The caning of Senator Sumner signalled the end of an era of compromise and sectional accommodation in the Senate, further heightening the discord that culminated in war after eleven southern states seceded from the Union during the winter of 1860-1861.
For further reading:
Donald, David Herbert, Charles Sumner and the Coming of the Civil War (Chicago: University of Chicago Press, 1960; reprinted 1987)
Donald, David Herbert, Charles Sumner and the Rights of Man (New York: Knopf, 1970)