One of eight children, Jeno was born to religious Jewish parents in the northeastern Hungarian town of Buj. The family later moved to the village of Zalkod, where Jeno's father ran a general store. His schooling over, Jeno became a cabinet maker. After he married, he and his wife Eloise settled down in Sarospatak, a picturesque town with a ruined medieval fortress and the Windischgratz castle.

1933-39: Jeno's sister Sadie, who had emigrated to the United States, came to visit her parents in Zalkod. At the time, Jeno and Eloise had two children named Ersika and Zali. The reunion was joyous, despite Sadie's fears. On the trip over, their ship, the Bremen, had stopped in Hamburg, and Sadie had been terrified to see Nazis marching in the streets.