The first treaty the United States signed with the Yankton people took place at
Portage des Sioux on July 18, 1815. The second took place in Washington D.C., on October 21, 1837, and is recorded as Indian Treaty 226. By the late 1850s, pressure to open up what is now southeastern South Dakota to white settlement had become very strong. Struck-by-the-Ree and several other headmen journeyed to Washington, D.C., in late 1857 to negotiate a treaty with the federal government. Also in 1857 the Yankton secured the release of two captives taken by
Ink-pa-du-tah's band at the
Spirit Lake Massacre. The
Sisseton and Wahpeton tribes signed the
Treaty of Traverse des Sioux, ceding lands west to the
Big Sioux River. The Yankton Sioux claimed the land east of the Big Sioux River past the
Pipestone quarry. Both the Yankton and Yanktonai felt they Santee Sioux were collecting annuities that should have been theirs with the Yanktonai further claimed the Yankton tribe had sold Yanktonai land also.and cession. The
Yankton Treaty of Washington was signed April 19, 1858, with article 8 granting the Yankton a one-mile square
reservation protecting the pipestone quarry. but the problem continued and with little outside support, the Yankton people went to the
U.S. Supreme Court in 1928 to protect their rights and land. A hundred acres of the reservation were taken for the construction of the
Pipestone Indian school in 1894. Native American children were sent to the school until its closure in the 1950s. The Supreme Court ruled that when the Government took that land for the school it had actually taken the entire reservation and that the tribe should be compensated. At that point, the Pipestone reservation was on its path to becoming a National Monument. For about , a payment of approximately $1.6 million ($ in modern dollars) in annuities was to be paid over the next 50 years. Specific provisions of the treaty called for educating the tribe to develop skills in
agriculture,
industrial arts and
homemaking. This provided the purpose for construction of the school. The treaty stipulated that the tribe relocate to a reservation on the north side of the
Missouri River in what is now
Charles Mix County, named for the commissioner who signed the 1858 treaty for the federal government.) The
Senate ratified the treaty on February 16, 1859, and President
James Buchanan authorized it ten days later. On July 10, 1859, the Yankton Sioux vacated the ceded lands and moved onto the newly created reservation. After then there are three cessions on record: cessions 410, 411, and 412, all reducing the size of the reservation. In the 1990s a dispute between the tribe and the state led to the reservation's reduction to its current size. The state had issued a permit for a new
landfill to be built on land the tribe argued was on the reservation, based on its original boundaries, and thus the landfill had to meet federal standards, which it did not. It sued the state in federal court to block the project. In its defense, the state pointed to an 1894 act of Congress that had modified the 1858 treaty in the wake of the
Dawes Act seven years earlier accepting an agreement with the Yankton Sioux to sell to the federal government all the lands not allotted to members of the tribe. In 1998
the case reached the Supreme Court, which unanimously
held for the state, finding no evidence that Congress had intended to retain the reservation boundaries in existence as of 1894. In 2011, after years of
litigation, the Supreme Court ruled in favor of the Yankton people by determining that
"the Yankton Reservation had not been disestablished". ==Archery==