US calvary general whose unwise and reckless conduct got him and over 200 soldier of the seventh cavalry killed at the battle of little big horn.

George Custer

Explanation:

George Armstrong Custer was a Lt. Colonel of the United States Army 7th Cavalry Unit. He was killed at the battle of little big horn; a battle which Custer and his men never had a fighting chance, with the Indians winning the battle in less than an hour, killing Custer and 210 soldiers in the process. The battle was to gain control of Western territories also considered as the Sioux Wars.