A Pokémon League, generally speaking, refers to a competition between Pokémon Trainers. There are four known Leagues: the Indigo League in the Kanto region, the Orange League in the Orange Islands, the Johto League in the Johto region, and the Hoenn League in the Hoenn region. To join a League and participate in competitions, Trainers must acquire a certain number of Badges signifying the defeat of the region's Gym Leaders.

More specifically, The Pokémon League may refer to the Indigo League.

Leagues are perhaps the closest thing to a government in the Pokémon World. The Elite Four seem to hold great authority.

Types of competitions

There are two types of League competitions.

Competitions against the Elite Four

Qualifying trainers can choose to battle against the Elite Four for the title of Pokémon Champion. Trainers must defeat--consecutively--each member of the Elite Four in a six-on-six battle. If the trainer can also defeat the current reigning Champion in addition to the Elite Four, he or she will take over the title of League Champion.

The Indigo and Johto Leagues share a single Elite Four and Champion that meet on Indigo Plateau. The other Leagues each have their own Champion.

This route is typically used in the games.

Championship competitions

Periodically, League competitions will be held for qualifying Trainers from around the region to come together and battle their Pokémon. There are perhaps hundreds or thousands of trainers that participate in these competitions. Winning Trainers will move up to compete with a smaller pool of other highly skilled Trainers. The person to defeat all other Trainers will be deemed the winner of the competition and receive world-wide acclaim, among other things. Losing trainers who participate in the competitions will be ranked accordingly.

The rules vary from League to League and competition to competition. For example, in the Orange League competition, regardless of ranking, the winner of the general rounds will have to fight Drake.

This kind of competition is found in the Anime.