Aleksander Kolacio was the brother of the renowned town planner and architect Zdenko Kolacio.
He studied singing in the class of Professor Milan Reizer at the Academy of Music in Zagreb, and with A. Anceschi in Milan.
He began his career in 1934 with a solo concert in Sušak, and made his opera debut in 1935 in Ljubljana. In the period from 1936 to 1938 he was a member of the Ljubljana Opera, and from 1938 to 1941 a member of the Belgrade Opera. Afterwards he worked in Vienna, Prague, Zurich and Buenos Aires until 1945.
He also performed as an oratorio-type and concert singer, and became famous performing in operas by Verdi, Donizetti, Tchaikovsky, Puccini, Rossini, Ivan pl. Zajc.
He died in Argentina where he moved in 1948.
Grave location: TRSAT (B-3-30)