User blog comment:HigherPrim8/What was your first CoD game and what made you want to get another?/@comment-4559524-20100611224918

CoD4 after playing Halo 3, then started to play CoD series after CoD4, never played any CoD games that came before CoD4.

I would probably suggest Halo: Combat Evolved or Halo 2 before playing Halo 3. Those two games are the best to start with or else you will not get the main storyline basically.