The 1957 Treaty of Rome, which established the European Economic Community (EEC, now European Union), required member states to introduce gender pay equality (article 119).

Whilst the Equal Pay Act 1970 was the result of significant campaigning by women’s and labour organisations over a protracted period of time, it was also necessitated by EEC membership. Thus, the UK’s negotiations to join the EU were an important factor in paving the way for the Equal Pay Act. In the 1980s and 1990s, EU law went on to play a major role in the way the UK sex equality legislation developed. For example, both the Equal Pay Act 1970 and the Sex Discrimination Act 1975 were modified to comply with European Directives.