Final answer:
The Lakota Sioux, led by Sitting Bull and Crazy Horse, were the primary tribe involved in the Great Sioux Indian War, culminating in the famous Battle of Little Bighorn and ending with the Wounded Knee Massacre.
Step-by-step explanation:
The Lakota Sioux were the most involved tribe in the Great Sioux Indian War. The conflict is exemplified by the Battle of Little Bighorn on June 25, 1876, where the U.S. Army's Seventh Cavalry, under Colonel George Custer, was defeated by a coalition of Native American tribes, including the Lakotas, Cheyennes, and Arapahos. Prominent leaders like Sitting Bull and Crazy Horse played critical roles in the fierce resistance to westward expansion and U.S. military campaigns designed to suppress Native American insurgencies. Despite the successes at Little Bighorn, and continued resistance practices like the Ghost Dance, the Plains tribes were eventually subdued, leading to tragic events such as the Wounded Knee Massacre in 1890, effectively ending the Indian Wars.