At age thirteen, he played clarinet in a military band and later learned the alto saxophone, but, after moving to Stockholm in 1947, became a professional musician as a pianist.

He worked as a member of Arne Domnérus’s septet (initially co-led by the trumpeter Rolf Ericson) for two years from 1951;[3] the group mainly performed at Nalen, a leading dance spot in Stockholm.

At the same time, Gullin began to work with visiting American musicians, recording with James Moody, Zoot Sims and Clifford Brown.

The next year, 1954, he won the best newcomer award in the American DownBeat magazine,[3] after two March 1953 Swedish sessions were leased and issued by Contemporary Records as a 10” LP.

During most of 1959, Gullin, was active in Italy, he played with Chet Baker again and with the jazz alto saxophonist (and businessman) Flavio Ambrosetti, making radio broadcasts with him in Lausanne, Switzerland.