Rietz was a mathematics graduate at OSU in 1899, and obtained his PhD from Cornell U in 1902. After 15 years on the faculty at U Illinois, he moved to the U Iowa, where Wilks was one of his research students. He was a founder of the IMS and its first President (1935). See also Rietz Lecturer.

http://www.maa.org/history/presidents/rietz.html Fuller biography and photograph.