Below is a partial list of mostly United States-based Roman Catholic activists:
* - Polish priest and workers' activist. *Carl A. Anderson, current Supreme Knight of the Knights of Columbus *Carlos Felipe Ximenes Belo-Nobel Peace Prize winning Archbishop linked to East Timorese independence. *William Bennett *Daniel Berrigan () *Philip Berrigan, anti-war activist *Leonardo Boff, Liberation Theology activist () *Bernadette Brady, Vice-President of the 's Board of directors *Joseph I. Breen, deceased; movie censor for Catholic Church (starting 1934) *Orestes Brownson, convert who spoke in favor of Catholicism, and against socialism in numerous works. * *William F. Buckley, Jr. - founder National Review; author of God and Man at Yale *José Burgos - Filipino priest and independence activist *Archbishop Raymond Burke *Ernesto Cardenal - priest linked to the Sandinista National Liberation Front () *Hugh Carey, former NY State Governor; member of the Catholic Campaign for America *César Chávez(deceased) - Mexican American labor and social activist *Linda Chavez, on Catholic League Board of Advisors() *Rev. Charles Coughlin (deceased) - Anti-Semitic radio priest *Dorothy Day (deceased) - Founded Catholic Worker movement () *Alfred Delp, Jesuit involved in resistance to Nazi Germany() *William A. Donohue - Head of Catholic League's Board of Directors *Rev. Robert Drinan, deceased - former U.S. Congressman from Massachusetts *Rev. Philip Eichner, on Catholic League Board of Directors() *Black Elk, convert - Spiritual leader of his people () *Mike Ferguson, Congressman from New Jersey and former Executive Director of the Catholic Campaign for America. *Edwin Feulner - Helped found the Heritage Foundation *Maggie Gallagher - Columnist opposed to Same-sex marriage, assisted suicide, abortion, and pornography () *Mary Ann Glendon - Catholic League Board of Advisors() *Dolores Bernadette Grier, African-American convert - opponent of abortion rights *Scott Hahn - convert; Catholic apologist () *Helen Hull Hitchcock - Conservative convert and opponent of ordination of female priests *Deal Hudson - convert; founder Crisis, a magazine for conservative Catholics (fell out of grace due to a scandal) *Saint Alberto Hurtado- Member of the Society of Jesus who was active in the labor movement in Chile () *Karl Keating - Catholic writer and apologist who created Catholic Answers *Charles Kekumano (deceased) - activist Hawaiian priest *Alan Keyes - Catholic League Board of Advisors(). *Alex Koroknay-Palicz - Executive Director of the National Youth Rights Association *Lawrence Kudlow, convert; television journalist and economist *Bowie Kuhn (deceased) - Ave Maria Mutual Funds *Archbishop William Joseph Levada, Vatican-based conservative *Angelo Liteky - former priest, soldier, activist *Juli Loesch - Operation Rescue activist (raised Catholic; left church and then returned) *Rev. Daniel Lord, S.J., deceased; movie censor for Catholic Church in 1920s and early 1930s *Alphonse J. Matt Jr., current publisher of The Wanderer, a Catholic fundamentalist paper founded in 19th Century by his family *Michael Moore anti-war activist *Rev. C. John McCloskey, III, STD, Opus Dei activist; helps to convert influential individuals (Robert Novak, Larry Kudlow, Sam Brownback, et al) *Norma McCorvey, convert; activist pro-lifer (who originally was "Roe" in Roe v Wade *Rev. Sean McManus - County Fermanagh-native Irish nationalist and political activist; created MacBride Principles *Thomas Monaghan - multimillionaire (from Domino's Pizza) who established () Ave Maria Radio,, () and the Ave Maria School of Law *Mother Angelica, created Eternal Word Television Network *Dr. Bernard Nathanson, convert; went from pro-choice doctor to anti-abortion activist *Tadeusz Pacholczyk, anti-stem cell and pro-life Catholic priest *Frank Pavone () - Priests for Life *Michael Novak, conservative activist and writer; on Board of Ave Maria Mutual Funds () and the Catholic League () *Kate O'Beirne - Conservative writer and pundit; on Catholic League Board of Advisors () *Georges Pire - "Peace University" and Nobel Peace Prize for work with refugees () *Sister Helen Prejean - anti-death penalty activist (portrayed in movie Dead Man Walking by actress Susan Sarandon) *Martin Quigley, deceased - leading movie censor for Catholic Church (starting 1934) *Patrick Reilly, Cardinal Newman Society *Jane Sullivan Roberts, Feminists for Life (wife Supreme Court Chief Justice John Glover Roberts, Jr.) *Archbishop Óscar Romero of El Salvador, assassinated *Phyllis Schlafly - Conservative anti-ERA, anti-abortion activist; Board of Ave Maria Mutual Funds () and the Judeo-Christian Council for Constitutional Restoration *Bishop Bernard Sheil, deceased - known as "Labor's bishop" or "the people's bishop" *Jaime Cardinal Sin, deceased - involved in People Power Movement in The Philippines *Dr. Janet E. Smith - conservative educator and theologian; taught at University of Dallas *Mitch Snyder, deceased - convert; advocate for the homeless *Dinesh D'Souza - Conservative writer and columnist; on Catholic League Board of Advisors () *Sister Dorothy Stang - Roman Catholic nun murdered in Brazil for helping the landless and poor *Sister Rose Thering - During Vatican II helped in exonerating Jews from Christ's death; social and human rights activist *Christopher West, () Theology of the Body speaker and promoter. *Paul Weyrich, ultraconservative political activist; left Roman Catholic church over Vatican II, and is a Melkite Catholic deacon () * - connected to EWTN *George Weigel - Catholic writer and papal biographer; Catholic League Board of Advisors () *Thomas V. Wykes, Jr. - Co-founded Catholic Campaign for America