George Tyrrell was an Anglo-Irish Catholic priest and a highly controversial theologian and scholar. A convert from Anglicanism, Tyrrell joined the Jesuit order in 1880. His attempts to adapt Catholic theology to modern culture and science made him a key figure in the debate over modernism in the Catholic Church beginning in the late 19th-century. During the anti-modernist crusade led by Pope Pius X, Tyrrell was expelled from the Jesuit Order in 1906 and excommunicated in 1908.

Modernism in the Catholic Church describes attempts to reconcile Catholicism with modern culture, specifically an understanding of the Bible and Catholic tradition in light of the historical-critical method and new philosophical and political developments of the late 19th and early 20th centuries.