Geology went hard for uniformitarianism during the 19th century as a reaction against the earlier "catastrophist" worldview, which had interpreted all major land forms as consequences of the great global flood described in the Bible (or something like it). This yielded a strong preference for theories involving continuous processes operating over long spans of time, and skepticism of theories involving sudden, violent changes. This swung back to a better balance during the 20th century; with the ghost of Noah's Ark exorcised, the role of local "catastrophes" in geologic history could again be taken seriously.