Pope John XXIII called for Vatican II, which had a major part in shaping today's Church. I would say that the results of this council are much farther reaching than most non-Catholics would realize. The most visible of these changes includes the use of the vernacular instead of Latin in the Mass, as well as such things as the priest facing towards the people during the entire Mass, but the most important changes were those more theological in nature, as well as the Church's stance on other denominations.
