Shortly after Pope Pius X established the Diocese of Great Falls in 1904, Great Falls' first bishop, Matthias Lenihan, hired Montana architect John Hackett Kent to design a cathedral equal to those in Europe. Kent, who helped design the Montana state capitol, looked to thirteenth-century England for inspiration. St. Ann's shares all the features of the Gothic Revival style: an "exaggerated verticality" that makes the building itself look as if it were reaching toward heaven, a cruciform plan, pointed arches, window tracery, and a ribbed interior vault. According to the Great Falls Tribune, its red and cream sandstone was quarried locally, with "each block ... cut for a particular place in the structure and ... marked [to] ... designate it for that one particular place." Bitterroot Valley sculptor W. R. Gifford carved the two-ton exterior figure of Christ, which graces the top of the gable end arch. Construction of the cathedral, which seats five hundred people, cost approximately $100,000. Money for the project came from the four hundred parishioners living in Great Falls in 1906.