The <a href="https://en.wikipedia.org/wiki/Soviet_Union" id="mwAQ0" rel="mw:WikiLink" title="Soviet Union">Soviet Union</a> annexes <a href="https://en.wikipedia.org/wiki/East_Prussia" id="mwAQ4" rel="mw:WikiLink" title="East Prussia">East Prussia</a> as the <a href="https://en.wikipedia.org/wiki/Kaliningrad_Oblast" id="mwAQ8" rel="mw:WikiLink" title="Kaliningrad Oblast">Kaliningrad Oblast</a> of the <a href="https://en.wikipedia.org/wiki/Russian_Soviet_Federative_Socialist_Republic" id="mwARA" rel="mw:WikiLink" title="Russian Soviet Federative Socialist Republic">Russian Soviet Federative Socialist Republic</a>.<sup about="#mwt127" class="mw-ref reference" data-mw='{"name":"ref","attrs":{},"body":{"id":"mw-reference-text-cite_note-22"}}' id="cite_ref-22" rel="dc:references" typeof="mw:Extension/ref"><a href="./April_7#cite_note-22" id="mwARE" style="counter-reset: mw-Ref 22;"><span class="mw-reflink-text" id="mwARI">[22]</span></a></sup>
<span class="mw-reference-text" id="mw-reference-text-cite_note-22"><cite about="#mwt124" class="citation web cs1" id="mwCT0"><a class="external text" href="https://www.prlib.ru/en/history/619151" id="mwCT4" rel="mw:ExtLink nofollow">"Konigsberg (Kaliningrad) region formed in the RSFSR"</a>. <i id="mwCT8">Presidential Library</i><span class="reference-accessdate" id="mwCUA">. Retrieved <span class="nowrap" id="mwCUE">2022-01-10</span></span>.</cite><span about="#mwt124" class="Z3988" id="mwCUI" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Presidential+Library&amp;rft.atitle=Konigsberg+%28Kaliningrad%29+region+formed+in+the+RSFSR&amp;rft_id=https%3A%2F%2Fwww.prlib.ru%2Fen%2Fhistory%2F619151&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AApril+7"></span></span>