Область Войска Донского
Iosif Prut was born on November 18, 1900 in the city of Taganrog, in the Don Host Oblast of the Russian Empire. In 1901 his immediate family were diagnosed with acute tuberculosis and they travelled to Leysin, Switzerland, for a treatment in a local clinic. His father soon died of complications and was buried in Gerbersdorf, Germany. Iosif stayed in Leysin for treatment until 1908.