Efimas (Jefimas) Rozenbergas was born on 24 April 1921 in Minsk (Belarus). His father Davidas (b. 1894), who came from Žagarė, was a graduate of the Moscow Institute of Trade and a merchant; his mother Lėja Solomonov was born in 1898 in Smolensk. From 1929–1938, Efimas went to a gymnasium in the Gdansk municipality (Poland) and received his graduation certificate on 24 September 1938. The certificate indicated that he took his graduation examinations when he was no longer a pupil at the gymnasium. Around 1938, the family returned to Kaunas as citizens of Lithuania. Efimas tried to emigrate from Lithuania to the USA but the Second World War ruined his plans. In 1940, he became an auditor in the Faculty of Economics of Vilnius University. Like many other Jewish students, on 19 September 1941, he was expelled from the Faculty of Economics of Vilnius University on the basis of the Order of 17 September 1941 of the Higher Education Department of the Board of Education, which was subordinate to the Nazis and pursued their policies. He survived the Holocaust and in 1954 wrote to Vilnius University asking for a document regarding his studies at the Faculty of Economics in 1940/1941. The document was issued with the mediation of the Ministry of Foreign Affairs of the Lithuanian SSR. At that time, Efimas Rozenbergas was a citizen of Israel. He lived and worked in the kibbutz Hecer (Necer) in the Beer Jacob settlement in Israel.