What mistake by colonel george custer led to his defeat by chiefs sitting bull and crazy horse at the battle of little bighorn?

The correct answer is Custer and his force arrived ahead of the main U.S. force.

General George Custer's and his 7th Cavalry were defeated at the battle of the Little Bighorn, Montana, by the Sioux and Cheyenne Indians. Chief Sitting Bull and Crazy Horse commanded the Indian troops.

General Custer and his 264 men's were needed reinforcement in the battle but supporting U.S. columns failed to arrive on time and rescue them.

the answer is a) to be able to obey them.

d) he bring down boss tweed and tammany hall.