Bachelor, University of State of New York, Ossining, 1948; Bachelor of Sacred Theology, University of State of New York, Ossining, 1953; Master in Religious Education, Maryknoll Seminary, Ossining, 1953.
He served as the first Bishop of Incheon from 1961 to 2002. He was ordained a priest on June 13, 1953. After his ordination McNaughton studied the Korean language at Yale University.
He was sent to of Korea and was engaged in parish ministry in Chungbuk.
He served on the College of Consultors in the Diocese of Cheongju. He served as the Vicar General of the same diocese from 1959 to 1960.
Pope John XXIII named McNaughton the Titular Bishop of Thuburbo Minus and Vicar Apostolic of Incheon on June 6, 1961. William McNaughton was consecrated a bishop on August 24, 1961 by Cardinal Richard Cushing of Boston.
A year later on March 10 McNaughton was named the first bishop of the Diocese of Incheon.
He attended all four sessions of the Second Vatican Council (1962-1965). He held several positions in the Catholic Bishops" Conference of of Korea. McNaughton served as the conference secretary from 1965 to 1981 and as the president of the Committee for Liturgy from 1965 to 1970.
Pope John Paul II accepted Bishop McNaughton"s resignation as Bishop of Incheon on April 25, 2002.
He retired to his native United States.
He was a member of the Ecumenical Committee from 1970 to 1973 and its president from 1973 to 1978. He served as president of the Committee for Catechesis from 1978 to 1984 and as a member of the Episcopal Commission for Clergy and Religious from 1978 to 2002.