Sellery became a history instructor at the University of Wisconsin in 1901, and was later named a professor in 1909.[1] Sellery directed the UW summer session from 1906 to 1911, and as dean of the University of Wisconsin–Madison College of Letters and Science from 1919 to 1942, when he retired.[1] His salary as dean was $7,500.[2] Even as dean, he continued to give his history courses, which were popular.[3] He was known as a "team player", for his dedication, and he strongly defended faculty interests.[3] Sellery publicly denounced Alexander Meiklejohn and UW President Glenn Frank's Experimental College, which he saw as demeaning the faculty and their institution.[4] This created a rift between Sellery and Meiklejohn–Frank.[5]
Animosity between Sellery and Frank was longstanding. Sellery was rumored to be in line for the UW presidency before Frank's arrival.[6] Near the beginning of his term, Frank had a private investigator make files on Wisconsin key political and educational figures including Sellery.[6] Frank showed these files to Sellery, who noted that his own file wasn't "complimentary".[6] Frank attempted to fire Sellery in the first quarter of 1929, which backfired due to faculty alliance with the dean.[6] When the Board of Regents removed Glenn Frank in January 1937, Sellery served as acting university president for six months.[1]
Sellery died on his ninetieth birthday: January 21, 1962.[1]
