Which two Game Boy games first launched Pokémon in Japan?

Pocket Monsters Red and Green first launched Pokémon in Japan.

Game Freak released the two role-playing games for the Game Boy on 27 February 1996. They were designed as companion versions: each game contained Pokémon unavailable in the other, encouraging players to connect their systems and trade in order to complete their collections.

International audiences often know the first pair as Pokémon Red and Blue, but that was not the original Japanese pairing. Japan received Red and Green, while a revised Blue version later supplied the technical and graphical foundation for the overseas Red and Blue releases. The Japanese Green version therefore has a distinctive place in Pokémon history.

The games introduced the Kanto region, the original Pokédex, Gym challenges, Pokémon battles, and the goal of becoming Pokémon Champion. They also established the version-exclusive structure that continued through many later generations. Their shared-release model helped make communication between players part of the franchise's identity.