Unknown Ground

David Bronstein was born in Bila Tserkva, Ukrainian SSR, Soviet Union, to Jewish parents. Growing up in a poor family, he learned chess at the age of six from his grandfather. As a youth in Kiev, he was trained by the renowned International Master Alexander Konstantinopolsky. He finished second in the Kiev Championship when he was only 15, and achieved the Soviet Master title at the age of 16 for his second-place result in the 1940 Ukrainian SSR Chess Championship, behind Isaac Boleslavsky, with whom he became close friends both on and off the chessboard.


https://en.wikipedia.org/wiki/David_Bronstein