The Royal Rumble is an annual pay-per-view, produced every January by World Wrestling Entertainment (WWE) since 1988. It is one of the promotion's original four pay-per-views, along with WrestleMania, SummerSlam, and Survivor Series, dubbed the "Big Four". It is named after the Royal Rumble match, a modified battle royal in which the participants enter at timed intervals instead of all beginning in the ring at the same time. The match generally features 30 wrestlers, but 2011's instead had 40 and has thus far been the only Royal Rumble event to have 40 participants—it was the largest version of the match until the 50-man version that occurred at April 2018's Greatest Royal Rumble event. Traditionally, the winner of the match earns a world championship match at that year's WrestleMania. For 2011, the winner could choose to challenge for either Raw's WWE Championship or SmackDown's World Heavyweight Championship at WrestleMania XXVII. 2011 was the twenty-fourth event in the Royal Rumble chronology and featured wrestlers from the Raw and SmackDown brands. It was the last Royal Rumble to occur under the first brand split, which ended in August.