Roman Catholic clergyman John XXIII was born Angelo Guiseppe Roncalli. He was ordained a priest in 1904 and steadily rose through the Vatican heirachy.
He was the first permanent observer of the Vatican to UNESCO. Chosen to be Pope in 1958, John is perhaps best remembered for his 1962 convening of the Second Vatican Council, also known as Vatican II, an ecumenical meeting which called for greater unity in the Christian church. Vatican II ushered in tremendous reforms within the Roman Catholic Church.