Ben-Dov was born in Vilnius, then part of Second Polish Republic in 1924 and moved to the British Mandate of Palestine in 1935. He joined the Irgun, which was fighting the British for control of the region. When Lehi split from Irgun, Ben-Dov joined the former to continue fighting the British, who he didn't think were doing enough to try and stop the Holocaust. He was caught, imprisoned, and eventually exiled to Africa by the British. He returned to Israel after the establishment of the State of Israel in 1948, and fought in the IDF's 89th battalion.