Career
Millen was a dentist by profession, and served in the First World War with the Canadian Army Dental Corps. In Toronto he set up a practice on Danforth Avenue and became involved in the local community. He served as president of the Danforth Business Association.
In 1932 he ran for city council but failed to get elected.
He was finally successful in the 1937 election, winning a seat in Ward 1. Participant way through his first term Millen fell ill and died in April 1948.
The baseball stadium that then stood in Riverdale Park was named Millen Memorial Stadium in his honour.
