Dietz was born on August 17, 1884, in
Rice Lake, Wisconsin. His father William Wallace Dietz, settled in the area in 1871 and was elected county sheriff in 1877. His father married Leanna Ginder in November 1879. Dietz was an employee of and briefly claimed to attend Oklahoma's
Chilocco Indian Agricultural School. He left the school after appearing in one football game for them and did not graduate. He attended
Macalester College in
Minnesota in 1902 and 1903. Dietz enrolled at the
Carlisle Indian School in Pennsylvania beginning in 1907 and was a star player for their football team.
Contested heritage Dietz's heritage was first contested in 1916 after former neighbors who settled on the Pacific Coast heard he was posing as a Native American. In December 1918 the Federal Bureau of Investigation looked into his heritage after he registered for the draft as a "Non-Citizen Indian" with an allotment. The Bureau found he had taken on the identity of James One Star, an Oglala man of the
Pine Ridge Indian Reservation 12 years his senior who had disappeared in Cuba in 1894. Dietz also claimed he was the head of an American film company that produced propaganda films for the war. Dietz was tried in Spokane, Washington in June 1919 for the first offense. One Star's sister, Sallie Eaglehorse, testified after seeing him for the first time at the trial that Dietz was surely not her brother. In 1988, the
National Congress of American Indians attempted to meet and discuss the issue with the team's former owner,
Jack Kent Cooke, but Cooke refused a meeting. Researcher
Linda Waggoner traced Dietz's heritage in several articles in
Indian Country Today Media Network and at a 2013 symposium at the
National Museum of the American Indian. ==Playing career==