The Seminole Nation of Oklahoma is a federally recognized Native American tribe based in the U.S. state of Oklahoma. It is the largest of the three federally recognized Seminole governments, which include the Seminole Tribe of Florida and the Miccosukee Tribe of Indians of Florida. Its citizens are descendants of the approximately 3,000 Seminoles who were forcibly removed from Florida to Indian Territory, along with 800 Black Seminoles, after the Second Seminole War. The Seminole Nation of Oklahoma is headquartered in Wewoka within Seminole County, Oklahoma. Of 18,800 enrolled tribal citizens, 13,533 live in Oklahoma. The tribe began to revive its government in 1936 under the Indian Reorganization Act. While its reservation was originally larger, today the tribal reservation and jurisdictional area covers Seminole County, Oklahoma, within which it has a variety of properties.

The Seminole are a Native American people who developed in Florida in the 18th century. Today, they live in Oklahoma and Florida, and comprise three federally recognized tribes: the Seminole Nation of Oklahoma, the Seminole Tribe of Florida, and the Miccosukee Tribe of Indians of Florida, as well as independent groups. The Seminole people emerged in a process of ethnogenesis from various Native American groups who settled in Spanish Florida beginning in the early 1700s, most significantly northern Muscogee Creeks from what are now Georgia and Alabama.