Pokémon Battle Revolution was a standalone game released for the Wii. While it had some connectivity features with other Pokémon games like Diamond and Pearl, it was not a requirement to play. You could enjoy the game's features and battles without owning any other Pokémon game.
However, if you wanted to:
* Transfer Pokémon from Diamond/Pearl to Battle Revolution: You could use a Nintendo Wi-Fi Connection to transfer Pokémon from these games to Battle Revolution, allowing you to use them in battles.
* Access certain features: Some online events and features in Battle Revolution might have required you to have a compatible Pokémon game like Diamond or Pearl.
So, while it wasn't mandatory, having Diamond or Pearl did enhance the Battle Revolution experience by providing additional content and features.