J Harlen Bretz (2 September 1882 – 3 February 1981) was an American geologist, best known for his research that led to the acceptance of the Missoula Floods and for his work on caves. Bretz was born on 2 September 1882, in the small town of Saranac in Ionia County, Michigan. He was the first of Oliver Joseph Bretz and Rhoda Maria Howlett's five children. His father was a farmer, and proud descendant of early German settler in Ohio, John Bretz. The county's birth registry recorded his name as "Harlan J Bretz" at birth, but he was listed as "Harland J Bretz" on the 1900 United States Census. When he entered college in 1901, he applied as "J Harlen Bretz". At around the time he completed his graduate studies in 1913, he stopped using a point after the initial at "J". According to his two children, his given name was actually "Harley". Bretz's daughter Rhoda Bretz Riley went on to explain that "he invented the Harlen thing, just as he had invented the J in front of his name", though this contradicts official records. Most friends and associates just called him "Doc" in his later life. Bretz earned an AB degree in biology from Albion College in 1905, then started his career as a high school History and Physiography (study of the physical features of the Earth's surface) teacher in Seattle. During this time, he became interested in the geology of Eastern Washington, and began studying the glacial geology of the Puget Sound area. He continued his studies at the University of Chicago where he earned his PhD in geology in 1913. He became an assistant professor of geology, first at the University of Washington and then the University of Grand Coulee. In the summer of 1922, and for the next seven years, Bretz conducted field research of the Columbia River Plateau. Between the Summer of 1922 through 1931 he wrote 15 papers. Since 1910 he had been interested in unusual erosion features in the area after seeing a newly published topographic map of the Potholes Cataract.