Sharecropping is a system in which an individual rents land from a plantation/farm owner. In return, the individual must give the plantation owner some of his crops as a form of payment. After paying for the land, the person renting the land can keep the excess goods/resources. This system was extremely popular in the United States after the Civil War. This is because many newly freed slaves were skilled in farming and needed a way to survive.
Not necessarily their land is not occupied right now but they still terrorize people. But it could have influenced the creation of such groups due to a foreign people with different beliefs and tradition came into their lands.