Douglas Harper's Etymology Dictionary
Usage examples of "pro-slavery".
Instead of simply deciding the controversy, the Supreme Court handed down an aggressively activist, judicially supremacist, pro-slavery decision.
It added to the ferment which the Pro-Slavery Oligarchists of the South--and especially those of South Carolina--were intent upon increasing, until so grave and serious a crisis should arrive as would, in their opinion, furnish a justifiable pretext in the eyes of the World for the contemplated Secession of the Slave States from the Union.
Frankly, I find it hard to see how a state can be both pro-slavery and antisecession, as persnickety Kentucky seems to be, but the Ancient is willing to take the most egregious abuse from the abolitionist Jacobins among the Republicans rather than offend the peace Democrats who still profess to be loyal.
Stanton had to engage in furious backtracking, growing connective tissue to the pro-slavery radicals through that foppish Massachusetts Senator, Sumner.
Northern Democrats had voted for the Free-soil candidate because of the alleged pro-slavery tendencies of their own party.
This was the view held by Jefferson Davis and the extreme pro-slavery leaders.
Three days after this event Brown and his sons with two or three others made a midnight raid upon their pro-slavery neighbors living in the Pottawatomie valley and slew five men.