The
Border Ruffians were pro-
slavery activists from the
slave state of
Missouri, who in 1854 to 1860 crossed the state border into
Kansas Territory, to force the acceptance of slavery there. The name was applied by
Free-State settlers in Kansas and
abolitionists throughout the North. Armed Ruffians interfered in territorial elections, and attacked Free-State settlements. This violence was the origin of the phrase "
Bleeding Kansas". The Ruffians contributed to the growing sectional tensions, and helped bring on the
American Civil War.