Ward and 66 other members of the Choctaw Nation (plaintiffs) received land allotments in Oklahoma under an 1898 act of the United States Congress. The allotted land was to remain tax free for 21 years. In 1908, Congress removed the tax exemption and declared that the allotted land was subject to taxation. Officials of Love County, Oklahoma (the county) (defendant) then started to tax the land. In prior litigation, the plaintiffs and other allottees brought multiple suits in state court to enjoin the taxation. The United States Supreme Court ruled in those cases that the tax exemption was a vested property interest that Congress could not repeal. While the state suits were pending, Love County continued to tax the allotted properties. The county demanded that the taxes be paid and threatened to sell the land if the taxes were not paid. The county also had a local statute requiring an 18 percent penalty for late taxes. The county had advertised and sold other similarly situated property. The plaintiffs paid the taxes under protest to avoid the penalty and sale of their properties. Love County officials knew of the pending state litigation at the time of taxation. The county forwarded some of the collected taxes to other government agencies. The plaintiffs then sued the defendants in state district court to recover the paid taxes, alleging they were collected through coercion in violation of federal law. The state district court ruled in favor of the plaintiffs. The Oklahoma Supreme Court reversed the judgment and held that the taxes were paid voluntarily and that there was no statutory authority to refund taxes voluntarily paid. The state supreme court also held that there was no authority to hold the county liable for taxes collected and turned over to other government agencies. The United States Supreme Court granted certiorari.