重返帝國（德语：Heim ins Reich；意为“回到帝国故土”）是阿道夫·希特勒在第二次世界大战期间奉行的外交政策。此政策于1938年开始，希特勒的倡议旨在说服所有居住在纳粹德国（例如奥地利、捷克斯洛伐克和波兰西部地区）以外的德意志裔人口努力從这些地区“重返”到大德意志帝國中。他還要求德意志人而且还要從自《蘇德互不侵犯條約》簽訂後不歸屬德國的波蘭東部地區西遷。重返帝國政策的對象主要是《凡尔赛條約》後新生的波兰以及其他德国大量居民居住的地区，例如蘇台德，但澤以及1939年10月6日以后的欧洲东南和东北地区。
^Lynn M. Tesser. Europe´s pivotal peace projects: Ethnic separation and European integration(PDF). March 2015 Issue 6. European Policy Analysis. [11 January 2017]. （原始内容(PDF)存档于13 January 2017）. Heim ins Reich, with approximately 600,000 Germans (Volksdeutsche) moving into designated areas [was approved by Hitler, in] a bevy of population exchange agreements in 1938-40 [including] in a 6 October 1939 Reichstag speech.
^ 2.02.1R. M. Douglas. Orderly and Humane: The Expulsion of the Germans after the Second World War. Yale University Press. 2012: 21 [2020-08-25]. ISBN 978-0300183764. （原始内容存档于2020-02-24）. In a keynote address to the Reichstag to mark the end of the 'Polish campaign', Hitler announced on October 6, 1939 ... the Heim ins Reich (Back to the Reich) program. The prospect horrified many ethnic Germans, much of whose enthusiasm for Nazism had been predicated on the expectation that the boundaries of the Reich would, as in the cases of Austria, the Sudetenland, and Danzig, extend to embrace them. The prospect of being uprooted from their homes to face an uncertain future not even in Germany proper, but in the considerably less salubrious environment of western Poland, was much less attractive. So far from rallying enthusiastically to the Führer's call, therefore, many Volksdeutsche greeted the declaration of the Heim in Reich initiative with a deep sense of betrayal.