The reservation system refers to a policy established by the United States government during the 19th century that allocated specific areas of land for Native American tribes, often resulting in the forced relocation of these communities. This system was designed to confine Indigenous populations to designated territories, often on less desirable land, as settlers expanded westward and sought to claim more territory. The reservation system played a crucial role in the conflicts between the U.S. government and Native Americans during westward expansion, as it aimed to control and assimilate Indigenous populations.