Born in Galicia in Austria-Hungary, Lamm attended school and university in Vienna, where he studied international trade and law, and gained a doctorate in jurisprudence. Whilst a student, he joined the Austrian branch of Tzeiri Zion. After the German invasion of Austria in 1938 he was arrested and sent to Dachau concentration camp. However, in 1939 he left Austria and made aliyah to Mandatory Palestine.