William Portier

Contact Information

William Portier

Professor; Acting Committee Chair of Doctoral Programs in Theology; Mary Ann Spearin Chair of Catholic Theology

  • Full-Time Faculty


William L. Portier serves as the Mary Ann Spearin Chair of Catholic Theology in the Department of Religious Studies. He came to the University of Dayton in 2003 after teaching for twenty-four years at Mount Saint Mary's University in Emmitsburg, Md., where he served as Chair of the Theology Department (1989-98), Henry J. Knott Professor of Theology (1997-2003), and helped design that school's nationally recognized core curriculum. He is the author of Isaac Hecker and the First Vatican Council (1985) and Tradition and Incarnation (1994), a widely-used undergraduate text in theology. He is also the editor or co-editor of three other books on U.S. Catholicism and has contributed nearly one hundred articles and reviews in the areas of theology, U.S. Catholic history, and Catholic higher education. His graduate courses in the areas of historical and systematic theology generally support the M.A. and Ph.D. programs and treat subject areas such as Americanism, Roman Catholic Modernism, and contemporary issues in theology in the U.S. His article "Here Come the Evangelical Catholics" was chosen by the College Theology Society for the 2005 Award for Best Journal Article.


  • Ph.D. Theology, Faculty of Theology, St. Michael’s College, in the University of Toronto, 1980
  • M.A. Theology, Washington Theological Union, 1972
  • B.A. Classics, major in philosophy, Loyola University of Chicago, 1969

Positions Held

  • University of Dayton, Religious Studies Dept., Distinguished Visiting Professor, Fall, 1999; Fall, 2000; Fall, 2001; Mary Ann Spearin Chair of Catholic Theology, 2003-present; Ph.D Program Director, 2011-present.
  • Mount Saint Mary’s College, Emmitsburg, MD, Theology Dept., 1979-2003.  Lecturer, 1979-80; Assistant Professor, 1980-86; Associate Professor, 1986-89; Professor, 1989-2003; Chair, Theology Dept., 1989-98; Henry J. Knott Professor of Theology, 1997-2003.
  • University of Toronto, Religious Studies Dept., Graduate Teaching Assistant, 1976-77.

Professional Associations

  • Academy of Catholic Theology, American Academy of Religion, American Catholic Historical Association, Catholic Theological Society of America, College Theology Society.

Research Interests

  • Historical Theology (modern period, nineteenth and twentieth-century U.S.)
  • Systematic Theology fundamental theology, Christology, ecumenical theology, especially with U.S. evangelicals.

Selected Publications


Divided Friends: Portraits of the Roman Catholic Modernist Crisis in the United States, 2013.

Editor with R. Scott Appleby and Patricia Byrne, Creative Fidelity, American Catholic Intellectual Identities. 2004.

Editor with Sandra Yocum Mize, American Catholic Traditions: Resources for Renewal. 1997.

Tradition and Incarnation, Foundations of Christian Theology. 1994.  Review Symposium in Horizons 22/1 (Spring 1995): 104-128.

Isaac Hecker and the First Vatican Council. 1985.  Reviewed in Catholic Historical Review 72 (October 1986): 665-66; Theological Studies 48 (June 1987): 401-402; Church History 57 (March 1988): 107-108.

Editor, The Inculturation of American Catholicism, 1820-1900, Selected Historical Essays. 1988.


"Here Come the Evangelical Catholics," Communio 31/1 (Spring 2004): 35-66. 2005 Award for Best Journal Article, College Theology Society.

"Church Unity and National Traditions: The Challenge to the Modern Papacy," in Bernard Cooke, ed., The Papacy and the Church in the United States, 1989. 1989 Award for Best Article, College Theology Society.

More than a hundred book chapters (8), articles and reviews in journals such as SR Studies in Religion/Sciences religieuses, Catholic Historical Review, Horizons, Thomist, Commonweal, Communio, U.S. Catholic Historian and reference works such as American National Biography, HarperCollins Dictionary of Religion, Biographical Dictionary of Christian Theologians, Dictionary of Christianity in America, New Dictionary of Catholic Spirituality, and New Westminster Dictionary of Church History.

Editorial Board

Communio, U.S. Catholic Historian

Grants and Awards 

Bicentennial Medal (with spouse), Mount Saint Mary’s University, 2008

President’s Medal, Mount Saint Mary’s College, 2003

Lilly Fellows Program Mentoring Grant, AY 2002-03

Lilly Fellows Program Summer Seminar Grant, June-July, 2000

Travel Research Grant, Cushwa Center for the Study of American Catholicism, University of Notre Dame, 1986