Hiraaca

The Hiraaca, whose name means People of the Willows, are the largest of the three village groups forming the Hidatsa, a Siouan tribe of the middle Missouri in North Dakota; Hidatsa was originally one village's name. Their earliest Knife River villages date to the thirteenth century; pushed from Devils Lake by the Lakota, they settled beside the Mandan and built earth-lodge towns whose corn surplus made them a plains trade hub. The Crow split off from their nomadic bands.

Smallpox in 1782 broke their power, and around 1790 the Sioux besieged Big Hidatsa without taking it. In 1800 a raiding party captured the Shoshone Sacagawea, and Lewis and Clark wintered at their Knife River villages in 1804.

They made peace with the United States in 1825, George Catlin and Karl Bodmer painted them in 1832 and 1833, and smallpox in 1837 left roughly five hundred survivors.