Part 42: Release OverviewSide Notes #01: Release Overview
After the absolutely ridiculous success of the first two generations, money and fan expectations were expecting a new entry in the series. While Pokemon gave the Gameboy life, it was succeeded by the GBA, so Pokemon moved onto the new system and all the technological advancements that came with it. There's a lot here that's improved from previous games, but a huge amount of it was behind the scenes, so it made the games completely incompatible with previous ones.
So when Ruby and Sapphire came out in November 2002, only 200 Pokemon out of 386 could be obtained and those you've obtained in previous games can't be moved forward. It sucked and coupled with the lack of the day/night changes and real distance from the previous regions and characters, the new generation didn't start on the right foot. What was there was super good, but it wasn't perfect.
Thankfully, this was alleviated somewhat on January 2004 when FireRed and LeafGreen, remakes of the original Red and Green, were released, with updates to Kanto, making loads of Pokemon available again, including a chunk of Johto mons, and sticking to the original games pretty closely, for better or for worse. It also introduced the Wireless Adapter, which was a pretty neat device. There was also the e-Reader, in 2002, but it didn't sell well, so by the remakes it had been discontinued in America.
Surrounding the release of Gen 3, Pokemon Colosseum and XD: Gale of Darkness for the Gamecube were released on November 2003 and August 2005, respectively, allowing people to obtain the missing Johto Pokemon much easier and focusing on sweet ass Double Battles. It could connect to the Gen 3 games and made getting certain rare mons a breeze, as well as letting you play on the big screen.
Finally, Emerald was released in September 2004, an enhanced version of Ruby and Sapphire, having more changes to the original story than Crystal and Yellow before it, but still not a huge amount to justify it. Still, at least it was a 3 year gap compared to 1. So yeah, those are the dates, on with the show!