What were the original Japanese Pokémon games called?

The original Japanese Pokémon games were called Pocket Monsters Red and Green.

Game Freak and Nintendo released the pair for the Game Boy in Japan on February 27, 1996. Like later Pokémon versions, Red and Green were closely related but contained version-exclusive Pokémon, encouraging players to trade with one another. Together, they introduced the basic collection, training, battling, and trading structure of the series.

An enhanced Japanese Blue version followed later. When the games were prepared for overseas audiences, Nintendo used the names Pokémon Red and Blue rather than translating the original Japanese pairing directly. The Japanese Green version therefore occupies a different place in franchise history from the international Blue version.

The title Pocket Monsters reflects Pokémon's original Japanese name. International releases shortened the name to Pokémon, with an accent added to help guide pronunciation. This naming history is why early Japanese game titles can be easy to confuse with later worldwide versions.