Kammala jumla mai zuwa: Masarautar Prussia ta zama babbar jihar Daular Jamus bayan da aka kafa ta a 1871. Koyaya, Yarjejeniyar Versailles bayan Yaƙin Duniya na I ya ba da Yammacin Prussia ga Poland kuma ya sanya Gabashin Prussia wani yanki na Weimar Jamus (sabon Hanyar Poland ya raba Gabashin Prussia daga sauran Jamus), yayin da yankin Memel ya rabu kuma Lithuania ta haɗu da shi a 1923. Bayan nasarar da Nazi Jamus ta yi a Yaƙin Duniya na II a 1945, an raba Gabashin Prussia da yaƙi a kan dagewar Joseph Stalin tsakanin Tarayyar Soviet (Kaliningrad Oblast ya zama wani ɓangare na SFSR na Rasha, da kuma yankunan da ke cikin yankin Klaipėda a cikin Lithuanian SSR) da Jamhuriyar Jama'ar Poland (Warmian-Masurian Voivodeship). Babban birnin Königsberg an sake masa suna Kaliningrad a shekara ta 1946. Yawancin mutanen Jamus na lardin sun kasance
an kwashe su a lokacin yakin ko kuma an fitar da su ba da daɗewa ba bayan haka a cikin fitar da Jamusawa bayan Yaƙin Duniya na II. Kimanin mutane 300,000 (kusan kashi ɗaya cikin biyar na yawan jama'ar) sun mutu ko dai a cikin hare-haren bam na lokacin yaƙi, a cikin yaƙe-yaƙe don kare lardin, ko kuma ta hanyar zalunci da Red Army.