Editing European Union (section)

===Treaty of Rome (1958{{Non breaking en dash}}1972)===
{{Main|History of the European Communities (1958–1972)}}

[[File:Bundesarchiv Bild 183-45653-0001, Rom, Verträge über Zollpakt und Eurotom unterzeichnet.jpg|thumb|right|upright=1|Signing ceremony of the [[Treaty of Rome]] (1957), establishing the [[European Economic Community|EEC]]]]

In 1957, [[Belgium]], [[France]], [[Italy]], [[Luxembourg]], [[Netherlands|the Netherlands]], and [[West Germany]] signed the [[Treaty of Rome]], which created the [[European Economic Community]] (EEC) and established a [[European Union Customs Union|customs union]]. They also signed another pact creating the [[European Atomic Energy Community]] (Euratom) for cooperation in developing nuclear power. Both treaties came into force in 1958.<ref name="Europa History 45-59" /> Although the EEC and Euratom were created separately from the ECSC, they shared the same courts and the Common Assembly. The EEC was headed by [[Walter Hallstein]] ([[Hallstein Commission]]) and Euratom was headed by [[Louis Armand]] ([[Armand Commission]]) and then [[Étienne Hirsch]] ([[Hirsch Commission]]).<ref>{{Cite web |date=13 October 1997 |title=A European Atomic Energy Community |url=http://www.cvce.eu/obj/a_european_atomic_energy_community-en-19bc7f11-bea1-49c7-b534-18327c303f41.html |access-date=13 October 2013 |publisher=Cvce.eu}}</ref><ref>{{Cite web |year=2016 |title=A European Customs Union |url=http://www.cvce.eu/obj/a_european_customs_union-en-a11a5f17-d744-479e-ba75-2c70b6058608.html |website=cvce.eu}}</ref> The OEEC was in turn reformed in 1961 into the [[Organisation for Economic Co-operation and Development]] (OECD) and its membership was extended to states outside of Europe, the United States and Canada. During the 1960s, tensions began to show, with France seeking to limit supranational power. Nevertheless, in 1965 an agreement was reached, and on 1 July 1967 the [[Merger Treaty]] created a single set of institutions for the three communities, which were collectively referred to as the ''[[European Communities]]''.<ref name="ENA Merge">{{Cite web |title=Merging the executives |url=http://www.cvce.eu/obj/merging_the_executives-en-575850b6-f472-406a-936d-8c08a9e0db32.html |access-date=28 April 2013 |publisher=CVCE&nbsp;– Centre Virtuel de la Connaissance sur l'Europe}}</ref><ref>{{Cite web |date=7 August 2016 |title=Merging the executives |url=http://www.cvce.eu/obj/merging_the_executives-en-575850b6-f472-406a-936d-8c08a9e0db32.html |website=CVCE.EU by UNI.LU |language=en}}</ref> [[Jean Rey (politician)|Jean Rey]] [[President of the European Commission|presided over]] the first merged commission ([[Rey Commission]]).<ref>{{Cite web |title=The Commissioners – Profiles, Portfolios and Homepages |url=http://ec.europa.eu/archives/commission_2004-2009/index_en.htm |access-date=1 January 2022 |website=ec.europa.eu}}</ref>