Why did Sergey Prokofiev return permanently to the Soviet Union?

Sergey Prokofiev returned permanently to the Soviet Union primarily because he increasingly missed his homeland, despite enjoying material success and professional connections in the West.1

Although he had lived abroad for over a decade, Prokofiev maintained a strong connection to Russia. Following successful concert tours in the Soviet Union in 1927, 1929, and 1932, he decided to conclude his foreign obligations and move to Moscow permanently. He began the transition in 1933, gradually acclimating to the new conditions, and by 1936 he had closed his Paris apartment, effectively ending his period of emigration.12