Aharon Barak was born in Kaunas, Lithuania, the only son of Zvi Brick, an attorney, and his wife Leah, a teacher. After the Nazi occupation of the city in 1941, the family spent three years in the Kovno ghetto. At the end of the war, after wandering through Hungary, Austria, and Italy, Barak and his parents reached Rome, where they spent the next two years. In 1947, they received travel papers and immigrated to Palestine. After a brief period on a "moshav", the family settled in Jerusalem.