The Alola region is made up of four islands, along with one artificial island. Each of the four islands has a Pokémon called a guardian deity. These Pokémon are collectively called the tapu, and they are worshiped by the people. The kahunas who serve as leaders of each island are chosen by these island guardians. The guardian deity of Melemele Island is Tapu Koko.

Alola is surrounded by the sea. It has a diverse ecology made up of Pokémon that have lived as natives of the Alola region for generations, along with Pokémon that have more recently arrived in Alola from other regions.

In Alola, humans and Pokémon coexist in a very close relationship, and a culture has developed that is different from other regions.