Complex sentence: The Spirit Lake Tribe (in Santee Dakota: "Mni Wakan Oyate", formerly Devils Lake Sioux) is a federally recognized Sisseton Wahpeton tribe based on a reservation located in east-central North Dakota on the southern shores of Devils Lake.
Split into simpler sentences: The Spirit Lake Tribe (in Santee Dakota: "Mni Wakan Oyate", formerly Devils Lake Sioux) is a Sisseton Wahpeton tribe. Its reservation is located in east-central North Dakota on the southern shores of Devils Lake.