At that time, Delaware Indians were members of one of three clans or phratries: turtle, turkey, and wolf. Each division had its own chiefs, councilors, and war captains. The chief of the turtle phratry—the senior clan—served as principal chief of the tribe. In 1774, White Eyes replaced the aged Netawatwees as principal chief, and Gelelemend served as councilor of the turtle clan. With White Eyes and Captain Pipe (war captain of the wolf clan), Gelelemend signed a treaty with the United States in 1778. After the death of White Eyes later that year, Gelelemend became principal chief.
However, the Delawares were deeply divided over how to respond to the war, and bands led by Pipe and Buckongahelas broke away from the pro-American leadership of Gelelemend. By 1781, Gelelemend had been forced from power, and he turned against his own people, guiding Colonel Daniel Brodhead in an expedition to destroy the Delaware capital of Coshocton. With a few of his followers, Gelelemend returned with the Americans to Fort Pitt. He had become a man without a country. He remained at Fort Pitt until 1785, always in fear for his life.
Long interested in Christianity, Gelelemend joined the Moravian mission at Salem, Ohio in 1788. At the baptism ceremony, he took the name William Henry, after a man who had rescued him during the French and Indian War. He was the most prominent convert in the Christian Munsee community. Gelelemend died in Goshen, Ohio in 1811.