This brief timeline describes the proceedings leading up to and through the four working sessions of the Council.
25 Jan: Papal allocution by Pope John XXIII announcing his intention to conduct an Ecumenical Council.
17 May: Pre–preparatory phase begins with the formation of the Antepreparatory Commission (APC), headed by Vatican Secretary of State, Cardinal Tardini.
30 Jun: Cardinal Tardini, under instruction by Pope John, issues a letter to the worldwide Catholic episcopate and Catholic universities inviting suggestions for the agenda of the Council.
Apr: From September of the previous year responses, or vota, are submitted by the bishops and institutes of learning. Of 2812 individuals and groups consulted, 1998 bishops and 51 universities reply.
12 Mar: The vota at this time tallied to 9438 proposals; covering more than 2000 thematic subjects. This is summarized by the APC into an 18 page “Final Synthesis”.
05 Jun: Pope John issues motu proprio Superno Dei nutu outlining the procedure for the preparation phase for the Council.
06 Jun: 10 preparatory commissions are established, under the guidance of the Central Preparatory Commission (CPC) headed by the Pope himself.
09 Jul: Quaestiones based on the “Final Synthesis” are sent to preparatory commission chairmen to guide subsequent work.
Jul: CPC convenes for the first time to review the proposed documents, or schemata, submitted by the preparatory commissions.
25 Dec: Pope John formally summons the Council in the Apostolic Constitution Humanae salutis.
02 Jan: CPC sends 2856 invitations to eligible participants of the Council: 85 cardinals, 8 patriarchs, 533 archbishops, 2131 bishops, 26 abbots, and 68 religious superiors.
27 Jan: CPC amendment sub–commission is set up to review the re–submitted schemata of the preparatory commissions.
02 Feb: The opening date for the Council is announced. Until the Council opens in the fall, the CPC would have received 75 schemata and, through their work, reduced the number to 22.
1 Jul: Pope John calls the Church to penance and spiritual preparation for the Council in his encyclical Paenitentiam agere.
13 Jul: Pope John authorizes sending 7 schemata to the participating bishops for review: on the liturgy; on Christian unity; on social communication; on the sources of revelation; on preserving the deposit of faith; on Christian moral order; and on chastity, virginity, marriage, and the family.
05 Sep: Norms and procedures for the Council are laid out by the Apostolic Constitution Appropinquante concilio.
11 Oct: Arriving in Rome are bishops from 116 countries representing the continents of Europe (1041), North & South America (956), Africa (379), Asia (256) & Oceania (70). More than 500 are unable to attend due to travel restrictions. Pope John solemnly opens the Second Vatican Council with his allocution Gaudet mater ecclesia.
13 Oct: First session commences; Council Fathers call for more time to re–elect members to conciliar commissions.
16 Oct: Election of the 10 conciliar commissions, or working groups.
20 Oct: The Council issues the ‘Message to the World’ signaling its intent to demonstrate the Church’s solidarity with humanity and its attention on the major problems of the modern world.
22 Oct: Debate begins on liturgical reform. It is decided on 19 Nov to carry over the work into the next session.
14 Nov: Debate begins on the sources of revelation. Doctrinal differences emerge. Pope John adjusts voting procedure and creates a mixed commission of the Doctrinal Commission & Secretariat for Christian Unity to redraft the schema.
23 Nov: Debate begins on the schemata for social communication and Christian unity. The eagerly anticipated schema on the Church is distributed.
26 Nov: After three days of deliberations, the schema on social communication is approved, pending re–editing.
06 Dec: Pope John creates a Coordinating Commission to oversee the continuation of the work by the commissions during the recess. Headed by Secretary of State Cardinal Cicognani, this commission comprises Cardinals Confalonieri, Döpfner, Liénart, Spellman, Suenens, and Urbani.
08 Dec: First session closes; the Council adjourns.
03 Jun: Pope John XXIII dies.
17 Jun: Conclave opens to appoint Pope John’s successor.
21 Jun: Cardinal Montini is elected and, as Pope Paul VI, announces the continuation of the Council.
29 Sep: Second session commences. Press secrecy is lifted on public sessions.
15 Oct: After intense debate on the schema on the Church, Cardinal Suenens proposes a vote on the main disputed doctrinal points, which is accepted by the Presidents on 23 Oct, approved by Pope Paul, and taken on 30 Oct.
08 Nov: The Holy Office comes under criticism in the aula for appealing to the Pope to overturn the 30 Oct vote. The gap between the Council’s minority and majority widens.
04 Dec: Issued: Sacrosanctum concilium (Constitution on the Liturgy 2147/4); Inter mirifica (Decree on the means of Social Communication 1960/164). Second session closes; the Council adjourns.
04 Jan: Pope Paul VI meets Patriarch Athenagoras in the Holy Land.
17 May: Secretariat for Non–Christian Religions is established.
14 Sep: Third session commences with Paul VI concelebrating Mass with 24 Fathers. Representatives from the Orthodox Churches are present among the observers.
16 Sep: A reworked schema on the Church is debated, attention focuses on the doctrine of episcopal collegiality.
18 Sep: The schema on the Bishops is debated and sent back to the commission on 22 Sep.
23 Sep: Debate begins on the schema for religious liberty.
25 Sep: Debate begins on the schema on the Church’s relationship with the Jews.
30 Sep: The Council reviews the reworked schema on divine revelation. On 6 Oct it is decided to defer the vote on it to the following year.
5 Oct: Debate on the schema on ecumenism begins. Despite wide agreement, it remains buried under numerous requests for amendment and is sent back to the commission.
6 Oct: The schema for the Apostolate of the Laity is presented and found unsatisfactory. It is returned to the commission.
14 Oct: Both schemata on the life and ministry of priests and on the Eastern Churches is presented, found inadequate, and sent back to the commission for revision.
20 Oct: Schema XIII, on the Church in the world, is presented to the Council.
6 Nov: The Council reviews the schema on missionary activity. It is found unsatisfactory and returned to the commission after three days.
10 Nov: The schema on the renewal of religious life is presented, judged unsatisfactory and returned to the commission.
14 Nov: The “Black Week”: a strong sense of the dampening of the Council’s progress is felt. The bishops of the DC issue the Nota praevia to the schema on the Church.
17 Nov: The schema on Christian education fails to gain the Council’s approval, and is returned after two days.
19 Nov: Cardinal Tisserant announces a deferment on the vote on the schema on religious freedom.
21 Nov: Issued: Lumen gentium (Dogmatic Constitution on the Church 2151/5); Orientalium ecclesiarium (Decree on the Catholic Churches of the Eastern Rite 2110/39); Unitatis redintegratio (Decree on Ecumenism 2137/11). Third session closes; the Council adjourns.
7 Mar: The Secretariat for Nonbelievers is established, under the leadership of Cardinal König.
14 Sep: Fourth session commences.
15 Sep: Pope Paul VI issues apostolic constitution Apostolica sollicitudo, formulating norms for a new episcopal synod to be established to assist the pope in governing the Catholic Church. The schema on religious freedom reappears for discussion.
21 Sep: Schema XIII, reworked by 7 different groups, is debated until 06 Oct, reviewed again on 17 Nov and approved on 6 Dec. Elaborations on doctrine concerning family life is reserved to the Pope.
28 Oct: Issued: Christus dominus (Decree Concerning the Pastoral Office of Bishops in the Church 2319/1); Perfectae caritatis (Decree on Renewal of Religious Life 2325/1); Optatam totius (Decree on Priestly Training 2318/3); Gravissimum educationis (Declaration on Christian Education 2290/35); Nostra aetate (Declaration on the Relations of the Church to Non– Christian Religions 2221/88).
18 Nov: Issued: Dei verbum (Dogmatic Constitution on Divine Revelation 2344/6); Apostolicam actuositatem (Decree on the Apostolate of the Laity 2340/2).
04 Dec: Prayer service promoting Christian unity is held at St. Paul Outside the Walls.
07 Dec: Issued: Dignitatis humanae (Declaration on Religious Freedom 2308/70); Ad gentes divinitus (Decree on the Missionary Activity of the Church 2394/5); Presbyterorum ordinis (Decree on the Ministry and Life of Priests 2390/4); Gaudium et spes (Pastoral Constitution on the Church in the Modern World 2290/35). The sees of Rome and Istanbul nullify the mutual excommunications on one another declared in 1054.
08 Dec:: The Second Vatican Council is solemnly ended.