Final answer:
The last major event of the Indian Wars was the Wounded Knee Massacre in 1890, where between 150 and 300 Lakota men, women, and children were killed during an accidental rifle discharge by a young Lakota man.
Step-by-step explanation:
The last major event of the Indian Wars was the Wounded Knee Massacre in 1890. On their reservation, the Lakota people had been performing the 'Ghost Dance' which worried White settlers. The 7th Calvary prepared to round up the people performing the Ghost Dance, and when they caught up to them at Wounded Knee, the Lakotas prepared to surrender. However, an accidental rifle discharge led to indiscriminate firing by the U.S. soldiers, resulting in the massacre of between 150 and 300 men, women, and children.