Written By: Ben Cosgrove

As monumental as the election of a new pope has always been and always will be for Catholics around the world, other (very) occasional events in the life of the church often have far more wide-reaching and long-lasting effects. The pontiff is, of course, the supreme figure in the church’s hierarchy —but more than 260 men have held the title over the past two millennium, and only a relative handful of those figures have presided over historic changes in the ways Catholics worship and relate to both their local parishes and congregations and to the Holy See in Rome.

By contrast, for example, the Second Vatican Council (known colloquially as Vatican II) held at St. Peter’s between 1962 and 1965 was more significant in both its message and its spiritual and cultural ramifications than any single act or pronouncement by any pope of the past few centuries. The twenty-first Ecumenical Council of the Catholic Church, and only the second ever held at Saint Peter’s Basilica, Vatican II offered nothing less than an utterly new dialogue between the Roman Catholic Church and the modern world.

Opened in October 1962, when Pope John XXIII was pontiff, and lasting until December 1965, during the papacy of Pope Paul VI, Vatican II advanced both major and minor reforms to church doctrine and matters of faith, e.g., encouraging Catholics to pray with non-Catholic Christians; a new prominence (and power) for bishops within the church; the sanctioning of languages other than Latin during Mass, and more.

Here, LIFE.com recalls the historic, landmark Vatican II council with photographs by Hank Walker and Paul Schutzer.

Pope John XXIII rides in the procession to St. Peter's Basilica at start of the Second Vatican Ecumenical Council, 1962.

Pope John XXIII rode in the procession to St. Peter’s Basilica at the start of the Second Vatican Ecumenical Council, 1962.

Paul Schutzer The LIFE Picture Collection/Shutterstock

Scene in Rome during the Second Vatican Ecumenical Council, 1962.

Scene in Rome during the Second Vatican Ecumenical Council, 1962.

Paul Schutzer The LIFE Picture Collection/Shutterstock

Scene in Rome during the Second Vatican Ecumenical Council, 1962.

Scene in Rome during the Second Vatican Ecumenical Council, 1962.

Paul Schutzer The LIFE Picture Collection/Shutterstock

Scene in Rome during the Second Vatican Ecumenical Council, 1962.

Scene in Rome during the Second Vatican Ecumenical Council, 1962.

Paul Schutzer The LIFE Picture Collection/Shutterstock

Vatican Ecumenical Council and Ecumenical Procession, Rome, 1962.

The Vatican Ecumenical Council and Ecumenical Procession, Rome, 1962.

Paul Schutzer The LIFE Picture Collection/Shutterstock

Table of cardinals during the Second Vatican Ecumenical Council, 1962.

A table of cardinals during the Second Vatican Ecumenical Council, 1962.

Hank Walker The LIFE Picture Collection/Shutterstock

Prelates attend a party at the Chinese Embassy in Vatican City on the eve of Vatican II, 1962.

Prelates attended a party at the Chinese Embassy in Vatican City on the eve of Vatican II, 1962.

Paul Schutzer The LIFE Picture Collection/Shutterstock

Cardinals at a party held by Chinese ambassador, Rome, 1962.

Cardinals at a party held by the Chinese ambassador, Rome, 1962.

Paul Schutzer The LIFE Picture Collection/Shutterstock

Vatican Ecumenical Council and Ecumenical Procession, Rome, 1962.

The Vatican Ecumenical Council and Ecumenical Procession, Rome, 1962.

Paul Schutzer The LIFE Picture Collection/Shutterstock

Scene during the Second Vatican Ecumenical Council, 1962.

Scene during the Second Vatican Ecumenical Council, 1962.

Hank Walker The LIFE Picture Collection/Shutterstock

Pope John XXIII during the Second Vatican Ecumenical Council, 1962.

Pope John XXIII during the Second Vatican Ecumenical Council, 1962.

Hank Walker The LIFE Picture Collection/Shutterstock

Scene inside St. Peter's Basilica during the Second Vatican Ecumenical Council, 1962.

Scene inside St. Peter’s Basilica during the Second Vatican Ecumenical Council, 1962.

Hank Walker The LIFE Picture Collection/Shutterstock

Scene inside St. Peter's Basilica during the Second Vatican Ecumenical Council, 1962.

Scene inside St. Peter’s Basilica during the Second Vatican Ecumenical Council, 1962.

Hank Walker The LIFE Picture Collection/Shutterstock

Scene inside St. Peter's Basilica during the Second Vatican Ecumenical Council, 1962.

Scene inside St. Peter’s Basilica during the Second Vatican Ecumenical Council, 1962.

Hank Walker The LIFE Picture Collection/Shutterstock

Scene inside St. Peter's Basilica during the Second Vatican Ecumenical Council, 1962.

Scene inside St. Peter’s Basilica during the Second Vatican Ecumenical Council, 1962.

Hank Walker The LIFE Picture Collection/Shutterstock

Devout observers of procession of Catholic prelates entering St. Peter's during the Second Vatican Ecumenical Council, 1962.

Devout observers of the procession of Catholic prelates entered St. Peter’s during the Second Vatican Ecumenical Council, 1962.

Hank Walker The LIFE Picture Collection/Shutterstock

Pope John XXIII rides in procession to St. Peter's Basilica at the Second Vatican Ecumenical Council, 1962.

Pope John XXIII rode in a procession to St. Peter’s Basilica at the Second Vatican Ecumenical Council, 1962.

Paul Schutzer The LIFE Picture Collection/Shutterstock

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