Peter Kwasniewski

Peter Kwasniewski is an American Catholic author, lecturer and composer whose work centres on the traditional Roman liturgy, sacred music and the thought of Thomas Aquinas. He studied at Thomas Aquinas College and holds an M.A. and Ph.D. in philosophy from The Catholic University of America, with a specialisation in Aquinas (Catholicism.org; TAN Books). He was among the founders of Wyoming Catholic College in Lander, Wyoming, in 2006 and left it in 2018 to work independently as an author, speaker, editor, publisher and composer; he founded Os Justi Press, which publishes reprints of older works and new titles (peterkwasniewski.com).

Writing. His books include Tradition and Sanity (Angelico Press, 2018), a collection of dialogues and interviews (New Oxford Review), The Holy Bread of Eternal Life (Sophia Institute Press) and Turned Around (TAN Books, 2024), which replies to common objections to the traditional Latin Mass (TAN Books; Angelico Press). In April 2023 he launched Tradition & Sanity as a Substack, announced by New Liturgical Movement; his website now says most of his writing appears in Tradition & Sanity on Pelican+, and lists Rorate Caeli among the sites he contributes to (NLM; peterkwasniewski.com).

Public positions. After Leo XIV's election Kwasniewski argued, in comments reported by ACI Prensa and the National Catholic Register, that the new pope's only real option was to reverse Traditionis custodes openly rather than merely soften how it is applied (National Catholic Register; ACI Prensa). In November 2025 he argued that the restrictions had led to closures of communities and fewer places of worship (InfoVaticana). When the Society of St. Pius X announced consecrations in February 2026, he wrote that both a great good and a great evil were at stake (InfoVaticana). In a September 2026 interview with the German outlet Certamen, reported by InfoVaticana, he called for a return to the liturgical peace of Summorum Pontificum and argued that Cardinal Arthur Roche's July 2026 remarks should not automatically be taken as Leo XIV's definitive position (InfoVaticana). See Leo XIV and the Latin Mass.