Theodor Oberländer (1 May 1905 – 4 May 1998) was an Ostforschung scientist and German Nazi official and politician, who after the Second World War served as Federal Minister for Displaced Persons, Refugees and Victims of War in West Germany from 1953 to 1960, and as a member of the Bundestag from 1953 to 1961 and from 1963 to 1965.
Oberländer earned a doctorate in agriculture in 1929 and a second doctorate in economics in 1930. He spent time in the Soviet Union during the 1920s and early 1930s, including as an employee of DRUSAG (Deutsch-Russische Saatbau AG),
a German company involved in developing Soviet agriculture in cooperation with the Soviet government. Subsequently, he became active in Ostforschung, area studies of the Soviet Union, the Baltic states, Poland and other countries of Eastern and Central Europe, advocating elimination of Jews and subjugation of Polish people in Poland, which he characterised in his writings as having "eight million inhabitants too many". In 1933, he became Director of the Institute for East German Economy in Königsberg, and in 1938 he became Professor of Agriculture at the University of Greifswald. He served as a lieutenant in the German military intelligence service (the Abwehr) in the Soviet Union during the Second World War and was promoted to captain of the reserve before his discharge in 1943; in the same year he became Director of the Institute for Economic Sciences. From 1944 he was affiliated with the staff of Andrey Vlasov's collaborationist Russian Liberation Army. He became a member of the Nazi Party in 1933. However, from 1937 until the end of Nazi rule, he was under surveillance by the Sicherheitsdienst (SD), as he was suspected of disloyalty to the Nazi cause. In 1940, he endorsed the ethnic cleansing of Poland. He later became the leader of the mixed German and Ukrainian Nachtigall Battalion, as well as the German-Caucasian Bergmann Battalion (established in October 1941), which were active in anti-partisan warfare. Both groups were later accused of participation in war crimes.
After the war, the Americans held Oberländer as a POW. He worked with the American-sponsored Gehlen intelligence organisation (c. 1946 to 1948) as an expert on Eastern Europe.
He entered politics for the liberal Free Democratic Party from 1948. In 1950, he was a co-founder of the All-German Bloc/League of Expellees and Deprived of Rights and served as its chairman from 1954 to 1955. He served as a member of the Parliament of Bavaria from 1950 to 1953 and as Secretary of State for Refugee Affairs in the Bavarian Ministry of the Interior from 1951 to 1953. He then served as Federal Minister for Displaced Persons, Refugees and Victims of War in the Second and Third Cabinets of Chancellor Konrad Adenauer from 1953 to 1960, and as a Member of the Bundestag from 1953 to 1961 and from 1963 to 1965, during which time he represented Hildesheim from 1957 to 1961. In 1956, Oberländer became a member of the Christian Democratic Union (CDU). Oberländer was one of the most staunch anti-communists in the German government. He received the Grand Cross of Order of Merit of the Federal Republic of Germany, the Bavarian Order of Merit and the Legion of Honour.