The <a href="https://en.wikipedia.org/wiki/Maastricht_Treaty" id="mwAeA" rel="mw:WikiLink" title="Maastricht Treaty">Maastricht Treaty</a> takes effect, formally establishing the <a href="https://en.wikipedia.org/wiki/European_Union" id="mwAeE" rel="mw:WikiLink" title="European Union">European Union</a>.<sup about="#mwt52" class="mw-ref reference" data-mw='{"name":"ref","attrs":{},"body":{"id":"mw-reference-text-cite_note-8"}}' id="cite_ref-8" rel="dc:references" typeof="mw:Extension/ref"><a href="./November_1#cite_note-8" id="mwAeI" style="counter-reset: mw-Ref 8;"><span class="mw-reflink-text" id="mwAeM">[8]</span></a></sup>
<span class="mw-reference-text" id="mw-reference-text-cite_note-8"><cite about="#mwt49" class="citation web cs1" id="mwCE4"><a class="external text" href="https://european-union.europa.eu/principles-countries-history/principles-and-values/founding-agreements_en" id="mwCE8" rel="mw:ExtLink nofollow">"Founding agreements"</a>. Principles and values. <i id="mwCFA"><a href="./European_Union" id="mwCFE" rel="mw:WikiLink" title="European Union">European Union</a></i><span class="reference-accessdate" id="mwCFI">. Retrieved <span class="nowrap" id="mwCFM">10 April</span> 2022</span>.</cite><span about="#mwt49" class="Z3988" id="mwCFQ" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=European+Union&amp;rft.atitle=Founding+agreements&amp;rft_id=https%3A%2F%2Feuropean-union.europa.eu%2Fprinciples-countries-history%2Fprinciples-and-values%2Ffounding-agreements_en&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ANovember+1"></span></span>