I'm not sure what this is saying, but welfare preceded the end of slavery. The formalized system of welfare that we have drawn most from is that of the Elizabethan Poor Laws, first formalized in the 16th century. It was not about slaves or people of color, but thousands of poor whites in England displaced by industrialization, plagues, economic upheaval, etc. and wandering loosely through the nation. It was defined to force people to establish a year's residency somewhere in order to get aid. The colonists brought the idea with them and set up similar laws in the colonies, because, just an FYI, there are always people who can't make it economically or are disrupted by economic upheavals.