He was born into a well-off family - his father was a factory owner and wood salesman.
He joined the film business in 1915 as an established stage actor and became also very popular on the screen in no time.
When Prague was no longer a secure place he flew to Switzerland in 1938 and one year later he emigrated to Palestine.
His sister was the well-known actress Rosa Valetti, his niece Lotte Stein became an actress as well.
Hermann Vallentin brought his artistic ambition out with an acting training at the Königliches Schauspielhaus in Berlin, afterwards he gained a foothold at the Zentraltheater Berlin and appeared in different plays from 1895.