The island of Ireland is a sea-bound land-mass, and part of the British Isles, located in north-western Europe. Historically governed in its entirety by the United Kingdom (UK), the island was partitioned in the early part of the 20th century. The six counties in the north of the island known as Ulster remained part of the UK, becoming a constituent country known as Northern Ireland (NI), and a part of the larger 'United Kingdom of Great Britain and Northern Ireland' (GB&IE). The remaining counties of the larger southern regions of the island became a self-governing independent republic country, officially known as the Republic of Ireland (RoI, Eire, abbr: ie). Following Brexit, the Republic of Ireland will remain a full member state of the European Union (EU), whilst Northern Ireland will leave the EU at the same time as the United Kingdom.