The Ireland national rugby union team is the men's representative national team for the island of Ireland in rugby union. The team represents both the Republic of Ireland and Northern Ireland. Ireland competes in the annual Six Nations Championship and in the Rugby World Cup. Ireland is one of the four unions that make up the British & Irish Lions – players eligible to play for Ireland are also eligible for the Lions.
The Ireland national team dates to 1875, when it played its first international match against England. Ireland reached number 1 in the World Rugby Rankings for the first time in 2019; the team returned to number 1 for a second time on 18 July 2022, and have not relinquished top spot thru to the rankings of 2 October 2023. Eleven former Ireland players have been inducted into the World Rugby Hall of Fame.