What name was Pokémon’s game concept originally called before it became Pocket Monsters?

Pokémon’s game concept was originally called Capsule Monsters before it became Pocket Monsters.

Satoshi Tajiri developed the early idea around collectible creatures that could be stored and exchanged. The concept drew on his childhood insect collecting and on the Game Boy’s ability to connect two systems with a Game Link Cable. The planned name reflected the idea of creatures emerging from capsules.

The phrase Capsule Monsters could not be trademarked, according to accounts of the project’s development. The name was changed first in working usage and ultimately became Pocket Monsters, or Poketto Monsutā in Japanese. The international abbreviation Pokémon was later used as the brand name.

The early title is not the name of a released game. Pokémon Red and Green, the first completed games, launched in Japan in 1996. Capsule Monsters is therefore best understood as a development-era name for the concept that evolved into the franchise.