William P. Callahan

On Friday, June 11, 2010, Auxiliary Bishop Callahan was appointed Bishop of La Crosse by Pope Benedict XVI, succeeding Jerome Edward Listecki, who became Milwaukee's Archbishop. On August 11, 2010, Bishop Callahan was installed in office in the presence of the envoy of the Apostolic Nuncio, Archbishop Listecki of Milwaukee, Archbishop Dolan of New York, and then-Archbishop Raymond Leo Burke, who had been La Crosse's bishop in his first episcopal assignment.

Bishop Callahan previously served as an Auxiliary Bishop of the Archdiocese of Milwaukee. After the former Archbishop of Milwaukee, Timothy Michael Dolan, was named Archbishop of New York, Auxiliary Bishop Callahan was elected the Apostolic Administrator, or temporary leader, of the Archdiocese of Milwaukee. He served in this role until Pope Benedict XVI named La Crosse Bishop Listecki as the new Milwaukee archbishop on Saturday, November 14, 2009.

He is the first Conventual Franciscan ever to become a bishop in the United States, and the first auxiliary bishop to be named to the Archdiocese of Milwaukee since 1979. Following Archbishop Dolan's appointment to the Archdiocese of New York in February 2009, Callahan was elected as the diocesan administrator of Milwaukee on April 20, 2009. As such, he oversaw the daily administration of the Archdiocese until Pope Benedict XVI named Bishop Listecki as the new Archbishop of Milwaukee in November 2009.

On October 30, 2007, Callahan was appointed Auxiliary Bishop of Milwaukee and Titular Bishop of Lares by Pope Benedict XVI. He received his episcopal consecration on the following December 21 from Timothy M. Dolan (who was then Milwaukee Archbishop), along with co-consecrators Milwaukee auxiliary Bishop Richard J. Sklba and Archbishop John Myers (Archbishop of Newark, who had previously been Bishop of Peoria where Callahan had served).

Returning to Illinois, Callahan served as Director of Vocations for the Conventual Franciscans from 1978 to 1984. He was associate pastor (1984–1987) and later pastor (1987–1994) at Holy Family Church in Peoria. He was named rector and pastor of the Basilica of St. Josaphat in Milwaukee in 1994, and oversaw the basilica's $7.5 million restoration, which earned him a reputation as an able fundraiser. In 2005, he became spiritual director of the Pontifical North American College in Rome.

Callahan was ordained to the priesthood by Archbishop William Cousins on April 30, 1977. He was then assigned to the Archdiocese of Milwaukee, Wisconsin, where he served as curate at the Basilica of St. Josaphat from 1977 to 1978.

In 1969, Callahan entered the novitiate of the Conventual Franciscans in Lake Forest. He made his profession as a member of that religious order on August 11, 1970. From 1970 to 1973, he attended Loyola University in Chicago, from where obtained a Bachelor's degree in Radio and Television Communications. He earned a Master's in Divinity from St. Michael's College at the University of Toronto in 1976.

Callahan intended to enter Archbishop Quigley Preparatory Seminary after his graduation from grade school, but was denied admission. He instead studied at the Franciscan-run St. Mary Minor Seminary in Crystal Lake from 1964 to 1968, and then at Junior College in Chicago until 1969.

William Patrick Callahan OFM Conv DD (born June 17, 1950) is an American prelate of the Roman Catholic Church who has served as Bishop of the Diocese of La Crosse, Wisconsin, since 2010.