What was the Japan-only Nintendo 64 game that preceded the international Pokémon Stadium?

Pocket Monsters Stadium was the Japan-only Nintendo 64 game that preceded the international Pokémon Stadium.

It was released in Japan in 1998 and served as the first Stadium title. The game brought Pokémon battles into a three-dimensional Nintendo 64 environment, following the success of the Game Boy games.

The Japan-only title was more limited than the later international release. It supported only 40 Pokémon, whereas the later Pokémon Stadium used all 151 species from Pokémon Red, Blue, and Yellow. The expanded game was released in Japan in 1999 and then reached Western regions in 2000.

The naming creates a common confusion: the international Pokémon Stadium is effectively the successor to the Japanese Pocket Monsters Stadium, while the Japanese release was also treated as an earlier Stadium entry. Transfer Pak compatibility connected the Nintendo 64 game to Pokémon stored in the Game Boy cartridges.