Republic of IrelandThe Republic of Ireland is a nation in north-western Europe that forms most of the island of Ireland (with the remainder being Northern Ireland which is part of the UK). Celtic tribes settled in Ireland in the 4th century BC but many Irish have left over the centuries and today over 80 million people of Irish descent live outside Ireland. Ireland has won the Eurovision Song Contest more times than any other country and the Irish invented Halloween – originally the Gaelic festival of Samhain.