The British & Irish Lions is a rugby union team selected from players eligible for the national teams of England, Ireland, Scotland, and Wales. The Lions are a test side and most often select players who have already played for their national team, although they can pick uncapped players who are eligible for any of the four unions. The team tours every four years, with these rotating between Australia, New Zealand and South Africa in order. The most recent test series, the 2021 series against South Africa, was won 2–1 by South Africa.

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.