Rugby union in Wales is considered a large part of Welsh national culture. Rugby union is thought to have reached Wales in the 1850s, with the national body, the Welsh Rugby Union (WRU) being formed in 1881. Wales are considered to be one of the most successful national sides in Rugby Union, having won the most Six Nations Championships after England, as well as having reached 3 World Cup semi finals in 1987, 2011 and 2019, having finished 3rd in the inaugural competition and having finished 4th in 2011 in a repeat of the first third place play-off. The Welsh team of the 1970s is considered to be arguably the greatest national team of all time, prompting many experts in the game to suggest that had the Rugby World Cup existed during this period, Wales would be amongst the list of World Cup winners. As of November 2021, they are ranked 8th in the world.

Rugby union football, commonly known simply as rugby union or more often just rugby, is a close-contact team sport that originated at Rugby School in England in the first half of the 19th century. Rugby is simply based on running with the ball in hand. In its most common form, a game is played between two teams of 15 players each, using an oval-shaped ball on a rectangular field called a pitch. The field has H-shaped goalposts at both ends.