Which Pokémon games were the first main-series titles to support internet battles and trading?

Pokémon Diamond and Pearl were the first main-series Pokémon games to support internet battles and trading.

Released in Japan in 2006 for the Nintendo DS, Diamond and Pearl used the Nintendo Wi-Fi Connection to let players trade and battle online. Earlier games supported local communication through cables or short-range wireless features, but Diamond and Pearl expanded those interactions through internet connectivity.

The games introduced the Sinnoh region and 107 new Pokémon, bringing the National Pokédex total to 493. Their online systems were tied to the Nintendo DS’s built-in wireless capabilities and helped make global player interaction a standard expectation for later main-series releases.

Players could still use local communication, so the games did not replace traditional trading methods entirely. The important distinction is that Diamond and Pearl were the first main-series entries to provide internet-based trading and battling as a central feature. Later services and consoles eventually replaced the Nintendo Wi-Fi Connection.