inb4 isn't on the first post......
Well actually christianity spread 3 ways.
At first it spread with word of mouth and peaceful conversions.
Then rome adopted it and used it as it's conquest religion.
Then waaaaaaaay later missionary work was done. Half offense half peaceful, just depending upon what country did it.
Judaism really just spread with bloodline originally(them being "god's chosen people" according to them)., but the message was usually spread peacefully in industrial on.
Islam was spread in a violent manner yes, more "oppressive" than violent, but was still pretty violent for conversion's sake.(yes, lots of people died).
Islam isn't the only one to have ever spread through violence, it is the only one to encourage spreading the religion through violence in it's books and by it's prophet.