NEW YORK, NY.- One hundred and thirty-four years ago today, George Armstrong Custer and his 7th Cavalry were overwhelmed near the Little Big Horn River by warriors of the Lakota Sioux and Northern Cheyenne. No survivors remained among those who fought under Custer’s direct command and few physical artifacts of the battle were left on the field, the Indians carrying with them anything that might reflect on their prowess or prove to be of utilitarian use. But a cavalry guidon, or swallow-tail flag, was hidden under the body of a dead trooper and discovered three days after the battle by Sergeant Ferdinand Culbertson, who was assigned to a burial party. Today Sotheby’s announces that this sacred relic, emblematic of one of the most significant events in American history, will be offered for sale in October 2010: Custer’s Last Flag: The Culbertson Guidon from The Battle of the Little Bighorn. Since 1895, this fragile silk flag has been preserved at the Detroit Institute of