The German pianist and teacher, Robert-Alexander Bohnke, was the son of the composer, conductor and violist Emil Bohnke and the violinist Lilli Bohnke, born von Mendelssohn and thus direct descendant of Moses Mendelssohn. His parents died in 1928 in a tragic traffic accident. Robert-Alexander Bohnke and his two older brothers and sisters grew up therefore with their grandparents Marie and Franz von Mendelssohn in Berlin. His grandfather, a direct descendant of the philosopher Moses Mendelssohn and the composer Felix Mendelssohn-Bartholdy, was a banker and president of the Berliner Handelskammer.
Robert-Alexander Bohnke began to play piano at age 5. First he studied with Artur Schnabel's pupil Hansi Graudan; then, after he left Germany in 1933, with Hans Erich Riebensahm, another A. Schnabel's pupil. From 1939 to 1941 he was pupil of Vladimir von Horbowski. After the exams, which he passed in 1946 at the Uhland-Gymnasium in Tübingen, he studied at the Stuttgarter Musikhochschule, piano with Vladimir von Horbowski and composition with Georg von Albrecht. As a pupil of Vladimir von Horbowski he was grandchild pupil of Sergei Rachmaninov and Ferruccio Busoni. At age 20 he won 2nd Prize at the Competition of the Hessischen Rundfunks, in 1953 the Kranichsteiner Music Prize, and in 1956 the 1st Prize at the international piano competitions in Munich, Geneva and Veralli.
Following that Robert-Alexander Bohnke received many invitations to give concerts, and offers to broadcast and to record. There are however of only few recordings of Bohnke, since he put very soon the emphasis of his work on the university activity. In 1956 he became professor for piano at the Freiburger Musikhochschule, and continued to hold this post until the beginning of 1990's. Since he kept his leaving-place in Tübingen, where his family also lived, he moved weekly between Tübingen and Freiburg through Schwarzwald (the Black Forest). He was married twice and father of five children.