Christianity (Catholic,Orthodox, Celtic) 
      And it's heresies (heres some)
              Catharism
              The Heresy of Peter Waldo
              Lollardism
              The Hussite Heresy


Islam  (Sunni, Shiites)
      And it's heresies (heres some)
             The Khawarij
             The Isma'ilis
             The Druze


Judaism
                Note. Many would convert to Christianty, and of those
 many were simply pretending and still practice their faith in secret.
Keep in mind that many Jews were quite open in their faith during the crusades.

First find out where you want to be from, then pick a faith. Think of what you 
could achieve if you were of that setting and faith. Choose an era, then put 
everything together.

With some effort and research you should have no problem getting started.


     Note. We discourage Pagan personas as they are never realistic 
historically. They as an illiterate people could not record their 
practices and beliefs. What little is known about them was written 
by their enemies and they pretty much died out by the end of the 
Dark ages and predate medieval reenactment. Those that would be 
period would keep it secret and follow a "cover faith" as would most
 heretics as well. So if you really must play a Pagan, keep it 
general..don't invent or use invented modern 
" neo-historical paganism" that fill endless shelves at B.Daltons 
and use a cover faith. Research is the Key!

After all it's a Templar city in the medieval era.  Keep it 
intelligent, keep it realistic your not supposed to be a character
...but a real person of the era.


Disclaimer
We do not condone nor forbid any period faith mentioned above, our 
purpose it to simply state what faiths were realistic to the era.