The Breeders' Cup World Championships is an annual series of Grade I Thoroughbred horse races, operated by Breeders' Cup Limited, a company formed in 1982. From its inception in 1984 through 2006, it was a single-day event; starting in 2007, it expanded to two days. All sites have been in the United States, except in 1996, when the races were at the Woodbine Racetrack in Canada.

Thoroughbred racing is a sport and industry involving the racing of Thoroughbred horses. It is governed by different national bodies. There are two forms of the sport – flat racing and jump racing, the latter known as National Hunt racing in the UK and steeplechasing in the US. Jump racing can be further divided into hurdling and steeplechasing.