It was always used....by everyone ever before that time but even Confederates had consciences and some like Stonewall Jackson were conflicted, some like Robert E. Lee freed slaves. Slavery wasn't solely a white issue either. In 1860 Charleston, 120 black people owned slaves. Slavery was the norm with the Indians, norm with Arabs, norm with African tribes and still occurs in various places.

Slavery would have been outlawed shortly after the War of Secession regardless of the victor.