British musicologist Jim Samson described Štolcer-Slavenski as "undoubtedly one of a very small handful of truly major composers from South East Europe in the first half of the twentieth century".

His father gave him his first instruction in music, then in 1913 he entered the Budapest Conservatory[1] where his teachers included Zoltán Kodály,[4] Albert Siklós,[1] and Béla Bartók.

The rich folk music of his native region, Medjimurje in north-western Croatia, left a decisive impact on him, and his youthful fascination with the sounds of church bells and the intricate combinations of their upper partials greatly contributed towards the formation of his harmonic idiom.

Polytonality and bold dissonances occurred in his piano pieces as early as 1913, at a time when many southern Slav composers were still treating material borrowed from folk tradition in a predominantly Romantic way.

Such interests brought him close to the music of Kodály and Bartók, and his academic studies deepened the mastery of counterpoint, which remained a vital ingredient of his style.

He was equally attracted by the mystical and ritual aspects of music, as may be seen from Chaos, a movement from the unfinished Heliophonia, and Religiophonia, the latter generally considered to be his masterpiece.