The 2015 Rugby World Cup was the eighth Rugby World Cup, the quadrennial rugby union world championship. The tournament was hosted by England from 18 September to 31 October.  Of the 20 countries competing in the World Cup in 2011, there was only one change: Uruguay replaced Russia. This was the first World Cup with no new teams to the tournament.

Reigning champions New Zealand won the cup and defended their title by defeating Australia in the final 34–17; South Africa defeated Argentina to take third place. This was the first Rugby World Cup where no Northern Hemisphere team got beyond the quarter-finals.  New Zealand were the first team to retain their title, and the first to win for a third time.

The highly contested match between Japan and South Africa in the opening weekend, which Japan scored the winning try in the added minutes over heavily favoured South Africa, was widely considered as the "biggest shock" or "biggest upset" in the history of rugby.  As a result, much media attention was drawn right from the beginning of this tournament.  Hosts England were eliminated at the pool stage, after defeats by Wales and Australia; this was the first time in the tournament's history that a solo host nation failed to progress to the knockout stages, and only the second time any host nation failed to progress to the knockout stages.  Wales being the first host nation failing to progress to the knockout stages, when they were co-hosts in the 1991 Rugby World Cup.