Karl Olof Ottelin was born in Helsinki May 3rd 1917. Ottelin graduated high school in 1938 from the Svenska Normallyceum in Helsinki. The following year, Ottelin started his studies at Centralskolan för Konstflit, where he studied under many known artists, including Werner West. After finishing his freshman year, Ottelin was forced to put his studies on hold because of the war. He graduated as an interior designer in 1946, and Ottelin's first employments were as a furniture scribe, initially at Sopenkorpi Oy Lahti (1946-1947) and later at Majander's furniture store Oy Mobilia Ab in Helsinki (1947).
In 1948 Olof Ottelin was employed as a furniture architect at Stockmann's office of creative design, until 1953, when he was appointed Chief of Stockmann's furniture department. In 1955, Ottelin was chosen as Werner West's successor and was appointed Artistic Director of Stockmann's Interior Departments, until 1971.