Editing Romano Prodi (section)

===2004 enlargement and end of the mandate=== 
{{See also|2004 enlargement of the European Union}}
In 2004, his last year as Commission President, the European Union was enlarged to admit several more member nations, most formerly part of the [[Eastern Bloc|Soviet bloc]]. It was the largest single expansion of the [[European Union]] (EU), in terms of territory, number of states, and population to date; however, it was not the largest in terms of gross domestic product. It occurred on 1 May 2004.

The simultaneous accessions concerned the following countries (sometimes referred to as the "A10" countries<ref>{{Cite web |url=http://www.derbyshire.police.uk/Documents/Safety-Advice/Migrants/UKResidency.pdf |title=Essential information for new arrivals in Derbyshire |access-date=8 May 2017 |archive-url=https://web.archive.org/web/20181006213609/http://www.derbyshire.police.uk/Documents/Safety-Advice/Migrants/UKResidency.pdf |archive-date=6 October 2018 |url-status=dead }}</ref><ref>[https://www.theguardian.com/politics/blog/2014/jul/21/twenty-years-tony-blair-britain-iraq Twenty years of Tony Blair: totting up the balance sheet]</ref>): [[Cyprus]], the [[Czech Republic]], [[Estonia]], [[Hungary]], [[Latvia]], [[Lithuania]], [[Malta]], [[Poland]], [[Slovakia]], and [[Slovenia]]. Seven of these were part of the former [[Eastern Bloc]] (of which three were from the former [[Soviet Union]] and four were and still are members of the Central European alliance [[Visegrád Group]]), one of the former [[Yugoslavia]] (together sometimes referred to as the [[A8 countries|"A8" countries]]), and the remaining two were [[Mediterranean]] islands and former [[British Empire|British colonies]].

Part of the same wave was the [[2007 enlargement of the European Union]] that saw the accession of Bulgaria and Romania, who were unable to join in 2004, but, according to the Commission, constitute part of the fifth enlargement. The commission was due to leave office on 31 October 2004, but due to opposition from the [[European Parliament]] to the proposed [[Barroso Commission]] which would succeed it, it was extended and finally left office on 21 November 2004. When his mandate expired, Prodi returned to domestic politics.