Godfrey Diekmann, O.S.B. (1908-2002): Benedictine monk of St. John’s Abbey (Collegeville, Minnesota) and major shaper of liturgical renewal in the United States before, during and after Vatican II. Prior to the Council, he served as consultor to the Pontifical Preparatory Commission on the Liturgy. Having served as a peritus (theological expert) at the Council, he was very much involved in establishing the International Commission on English in the Liturgy (ICEL).

Cardinal Albert Gregory Meyer (1903-1965): Chicago archbishop and one of the Council presidents. He made important contributions to the Dogmatic Constitution on the Church, the Dogmatic Constitution on Divine Revelation and the Pastoral Constitution on the Church in the Modern World. He helped secure the approval of the Declaration on Religious Freedom.

Archbishop Marcel Lefebvre (1905-1991): French conservative at the Council who, shortly afterward, called into question many of its teachings. Eventually, he broke from the Church and started his own “traditionalist” movement.

Francis Xavier Murphy, C.Ss.R. (1914-2002): Redemptorist priest and peritus during the Council. Using the pseudonym of Xavier Rynne (Xavier was his middle name and Rynne was his mother’s maiden name) and writing in The New Yorker, he detailed intrigue, both on and off the floor of the Council. In 1990, he publicly admitted writing these articles, explaining: “If I died tomorrow, the Jesuits would claim the author was one of theirs, and the Redemptorists would be happy to let them claim him. Now that’s impossible.”

John Courtney Murray, S.J. (1904-1967): Jesuit priest and editor of the journal Theological Studies. His influence proved instrumental in drafting the Declaration on Religious Freedom (Dignitatis Humanae). (See "A U.S. Gift to the Council" for more on his role at Vatican II.)

Cardinal Alfredo Ottaviani (1890-1979): Head of the Holy Office (now known as the Congregation for the Doctrine of the Faith) and one of the Council’s leading conservative voices. At the Council, he headed the Theological Commission, which reviewed the texts of all other commissions.

Pope John XXIII (1881-1963): Convenor of the Second Vatican Council. He was beatified in 2000.

Pope Paul VI (1897-1978): Cardinal of Milan at the time, Giovanni Montini was one of the more influential Council fathers when it began in 1962. Upon the death of Pope John, he was elected to the papacy, saw the Council to its close and shouldered the huge responsibility of guiding its implementation.

Pope John Paul II (1920-2005): Karol Wojtyla came to the Council as the auxiliary bishop (later archbishop) of Krakow, Poland. He was profoundly influenced by the Council, reflected by the name he chose when elected pope in 1978 (John in honor of John XXIII and Paul in honor of Paul VI). He was active in many conciliar debates, most notably the question of religious freedom and the Church in the modern world.

Karl Rahner, S.J. (1904-1984): Jesuit priest and one of the Council’s leading periti, along with Yves Congar, O.P., Hans Küng, Henri de Lubac, S.J., and Edward Schillebeeckx, O.P.

Joseph Ratzinger (b. 1927): Peritus of Cardinal Joseph Frings of Cologne, Germany. In 2005 he became Pope Benedict XVI.

Cardinal Leon Suenens (1904-1996): Progressive archbishop of Mechelen-Brussel (Malines-Bruxelles), Belgium. As one of the four moderators of the Council, he helped shape its direction and substance.

Mary Luke Tobin, S.L. (b. 1908): Sister of Loretto and one of 23 women observers (and the only one from the United States) at the Council. In 1964, she was elected president of the Conference of Major Superiors of Women and attended the Council’s last two sessions. She worked on a subcommittee for the Pastoral Constitution on the Church in the Modern World and describes her experience in Hope Is an Open Door (Abingdon Press, 1981).