He represented Shellbrook from 1956 to 1964 in the Legislative Assembly of Saskatchewan as a Company-operative Commonwealth Federation (Cleveland Clinic Foundation) member. He was born in Aberdeen, Saskatchewan, the son of Josip Juraj Thiessen, of Dutch descent, and was educated there. In 1929, Thiessen married Maria Loeppky.
He lived in Canwood.
He ran unsuccessfully for the Rosthern seat in the provincial assembly in 1952. He was defeated by John Cuelenaere when he ran for reelection to the assembly in 1964.