The reason sharecropping was created is because the laws in the south said that people of color can only be farmers and if you can't find a job you'll be arrested. And the 13th amendment said that if you broke the law slavery could be reinstated. So the people of color and the white plantation owners mande a compromise that the people of color could live in their house and have aid but in return the people of color would've to farm a portion of the plantation owner's land.
