He attended what is now Carroll University, in 1925, but graduated from the University of Wisconsin–Madison, in 1927, where he was a member of the Chi Phi Fraternity.
Teacher, Viroqua (Wisconsin) High School, 1927-1929;
teacher, Madison (Wisconsin) Vocational School. Practiced law, Richland Center, until 1951. Enrolling officer Civilian Conservation Corps, 1933-1935.
Assistant district attorney Richland County, 1933-1935. City attorney Richland Center, 1933-1937, 42-44. Member Wisconsin Assembly, 1935-1951, speaker, 1939, 41, 43, Republican floor leader, 1945, 47, 49.
Mayor Richland Center, 1944-1951. Attorney general Wisconsin, 1951-1957. Governor Wisconsin, 1956-1958.
Practiced law, Madison, 1959-1960. Member 87th-93d congresses 3d District Wisconsin. Member house commission on foreign affairs, house select commission on small business;member Federal Election Commission, from 1975, chairman, 1976-1977.
Member of advisory com.on rules, pleadings, practice, procedure Wisconsin Supreme Court, 1945-1951. Member, secretary Wisconsin Legislation Council, 1949-1951. Member Wisconsin Judicial Council from 1951.
He was mayor of Richland Center from 1944 to 1951 and a member of the Wisconsin State Assembly from 1935 to 1951, and served as Speaker of the Assembly from 1939 to 1945. Thomson was a member of the Federal Elections Commission.
Married Helen Davis, June 6, 1936 (deceased 1973). Children: Patricia, Susan Thomson Turner, Vernon Wallace Junior.