Second Vatican Council
The Second Ecumenical Council of the Vatican, commonly known as the or , addressed relations between the Catholic Church and the modern world. The council, through the Holy See, was formally opened under the pontificate of Pope John XXIII on 11 October 1962 and was closed under Pope Paul VI on the Solemnity of the Immaculate Conception on 8 December 1965.
Christianity in the modern era
On 11 October 1962 Pope John XXIII opened the Second Vatican Council, the 21st ecumenical council of the Catholic Church. The council was "pastoral" in nature, emphasising and clarifying already defined dogma, revising liturgical practices, and providing guidance for articulating traditional Church teachings in contemporary times. The council is perhaps best known for its instructions that the Mass may be celebrated in the vernacular as well as in Latin