 Dimayev was born into a family of peasant farmers on October 1, 1908 in Urus-Martan.Despite their relative lack of wealth, the Dimayev family had traditionally been educated in music, as all of Umar's brothers and sisters played the accordion, and Umar would later recall that his younger sister Aruzha would be the one who supported and cultivated his musical abilities.Although their father discouraged Dimayev from playing the accordion, saying it discouraged the development of his son's masculinity, Aruzha gave away her own instrument to Dimayev and taught him how to play the accordion.