His early works ranged from rather severe neo-classical styles influenced by Shostakovich, Prokofiev, and Bartók. Pärt's oeuvre is generally divided into two periods. Although Estonia had been an independent Baltic state at the time of Pärt's birth, the Soviet Union occupied it in 1940 as a result of the Soviet- Nazi Molotov-Ribbentrop Pact and the country would then remain under Soviet domination-except for the three-year period of German wartime occupation-for the next 51 years. In this period of Estonian history, Pärt was unable to encounter many musical influences from outside the Soviet Union except for a few illegal tapes and scores. While studying composition with Heino Eller at the Tallinn Conservatory in 1957, it was said of him that "he just seemed to shake his sleeves and notes would fall out." By the time he reached his early teen years, Pärt was writing his own compositions. He began attending music school in Rakvere, where his family lived. Pärt's musical education began at age seven. Although his fame initially rested on instrumental works such as Tabula Rasa and Spiegel im Spiegel, his choral works have also come to be widely appreciated.
He is considered a pioneer of this style, along with contemporaries Henryk Górecki and John Tavener. Pärt is often identified with the school of minimalism and, more specifically, that of mystic minimalism or holy minimalism.