Which handheld console hosted the first Pokémon games in Japan?

The first Pokémon games in Japan were hosted on the Game Boy.

Pocket Monsters Red and Green were designed for Nintendo’s original Game Boy and launched there on February 27, 1996. The system’s link-cable capability was crucial to Pokémon’s concept because players could trade creatures and battle friends using two compatible systems.

The games were technically compatible with the monochrome Game Boy, although later revisions also worked on newer members of the Game Boy family. Pokémon Yellow followed in Japan in 1998 and was designed with stronger visual and character connections to the animated series.

A common mix-up is naming the Game Boy Color, because Pokémon became strongly associated with that system and later entries used its color hardware. However, the original Red and Green release predates the Game Boy Color. The Nintendo 3DS connection belongs to the 2016 Virtual Console re-releases, not the franchise’s first launch.