Assassin's Creed series

I'm looking for some advice/suggestions on this series of games, specifically for the Xbox 360. I have the original, and a played it for a few hours, but I remember getting stuck on horseback somewhere and never continued past that point.

So, my question is, are all the games related, like if I skipped ahead, would I miss key details? Which game is the easiest to play? I'm not someone who spends hours a day gaming. Which one involves the Civil War? I saw some screenshots for a game with Civil War soldiers in it.

You miss out on a bit but not to much if say its from the 1st one to the 2nd assassins creed since the 2nd one rarely mentions Altair at all and mainly focuses on Ezio.If it's from like assassins creed 2 and skiping to say revelations then yea you would miss some of the stuff that and be a little lost since you didn't play brotherhood. The one with the civil war is the new one that is going to come out called assassins creed 3 and starts with a totally new protagonist. So the ones with Ezio you will get lost if you skip around.The third one connects with the previous ones but I dont think you would miss too much but would miss out on how its going with Desmond and what happened to Desmond in the previous games,that's were you would miss out the most.Anyways new one comes out on october 30 2012 on the xbox so you got time to catch up if you want with the previous games.

Thanks! That's exactly the answer I was hoping for.