William Sumner was born in Peoria, Illinois, in 1892. He received a bachelor's degree in technical journalism from Kansas State Agricultural College in 1914 and a master's degree in journalism from the University of Wisconsin.
He joined the University of Wisconsin staff in 1915 as bulletin editor in the College of Agriculture, where he developed a program of teaching and research in agricultural journalism.
In 1951, he went to France as an information consultant to the Economic Cooperation Administration.
In 1954, he conducted a summer information training course in the Caribbean for the U. S. Department of Agriculture's Foreign Agricultural Service.
He was an honorary member of the Wisconsin Press Association, and a founding member of the Dane County (Wisconsin) Press Association.
He died in January 1960, in Madison, at the age of 67.