There are conflicting accounts of Harry Yount's place and date of birth. Ernest Ingersoll wrote that he was born in Susquehanna County, Pennsylvania, and different birth years have been mentioned by various writers, such as the anonymous author of a published biographical sketch who wrote that Yount was born in 1847, and Thomas J. Bryant, who interviewed Yount in the latter years of his life and who speculated that 1837 was his birth date in an article published in the "Annals of Wyoming", journal of the Wyoming State Historical Society. However, research undertaken by William R. Supernaugh, an employee of the National Park Service, found military enlistment papers, Yount's Army pension file, and the 1840 United States Census records, all of which indicate that Yount was born on March 18, 1839. These records also show that his legal name was Henry S. Yount. His lifelong nickname was "Harry", and his middle name is unknown.