Metrication in the Republic of Ireland happened mostly in the 20th century and was officially completed in 2005, with a few exceptions. The island of Ireland gradually adopted the British imperial measurement system, fully replacing traditional Irish measure during the 19th century, and these units continued to be used after the independence of the Irish Free State (1922) and the establishment of the Republic of Ireland (1937/49). The Irish Free State joined the Metre Convention in 1925. In 1980 the European Union asked all of its member states to convert to the metric system, and in Ireland and the UK this process was originally to have been completed by 2009. Metrication succeeded in Ireland with the changeover fully completed in 2005, with some exceptions.