
Between 2,000 and 2,500 bishops attended each Vatican II session inside St. Peter’s Basilica. The council produced 16 landmark documents that transformed the church.
Jan. 5, 1959 Pope John XXIII announced his intention to convoke an Ecumenical council.
May 17, 1959 Antepreparatory Commission appointed. Bishops, abbots, and superiors general asked to submit suggestions for subjects to be considered by the council.
May 5, 1960 Preparatory Commissions appointed to prepare schemas for Council documents. Pope creates Secretariat for Promoting Christian Unity.
Feb. 2, 1962 Pope John XXIII announces starting date of council as Oct. 11, 1962.
July 20, 1962 Non-Roman Christian churches invited to send delegate-observers to council.
Oct. 11, 1962 First session of Second Vatican Ecumenical Council opens. Dec. 8, 1962 First Session ends. Drafts of Constitution on Liturgy, Constitution on Divine Revelation, Constitution on the Church and Decree on Social Communications debated and returned to Commissions for second draft. No documents approved.
June 3, 1963 Pope John XXIII dies.
June 21, 1963 Cardinal Giovanni Montini elected pope, takes name of Paul VI, vows to continue council.
Sept. 29, 1963 Second Session of Second Vatican Ecumenical Council opens.
Dec. 4, 1963 Second Session ends. Constitution on the Liturgy and Decree on Social Communications approved and promulgated by pope.
May 17, 1964 Pope creates Secretariat for Non-Christian Religions.
Sept. 14, 1964 Third Session of Second Vatican Ecumenical Council opens.
Nov, 21, 1964 Third Session ends. Dogmatic Constitution on the Church, Decree on Ecumenism and Decree on Eastern Catholic Churches approved and promulgated by pope. April 8, 1965 Pope Paul VI creates Secretariat for Relations with Non-believers.
Sept. 14, 1965 Fourth Session of the Second Vatican Ecumenical Council begins.
Dec. 8, 1965 Fourth Session ends. Dogmatic Constitution on Divine Revelation, Pastoral Constitution on the Church in the Modern World, Decrees on Pastoral Office of Bishops, Lay Apostolate, Priestly Formation, Renewal of Religious Life, Missionary Activity of the Church, Priestly Life and Ministry, Declarations on Christian Education, Religious Liberty, and Non-Christian Religions approved and promulgated by Pope Paul VI.
Dec. 8, 1965 Pope Paul VI declares Second Vatican Ecumenical Council concluded.