Prior to Francis, the last pope we had from a religious order (as opposed to a career diocesan) was Gregory XVI in 1831. Now we've had two religious popes in a row --- Francis, a Jesuit, and then Leo, an Augustinian.
There are a few different orders within the catholic church with some of their own intellectual, practical and traditional differences. Most popes don't come from any of the orders. The last two popes did. That's historically odd. Francis had been the first one from his order ever, even though it's the largest one.