From Bulbapedia, the community-driven Pokémon encyclopedia.
The Unova League (Japanese: イッシュリーグ Isshu League) is the regional Pokémon League of the Unova region. The Unova League is composed of the Unova Gym Leaders and the Unova Elite Four, along with the League Champion. Pokémon Trainers who earn eight Gym Badges by defeating the Gym Leaders of the Unova League qualify to challenge the Elite Four located in the Pokémon League building.
In the anime, Trainers who collect eight Badges are eligible to enter Unova's championship competition, the Vertress Conference.