Catastrophism is the idea that Earth has been affected in the past by sudden, short-lived, violent events. Catastrophes, possibly worldwide in scope, came between long periods of quiet inactivity. This was called 'catastrophism' by William Whewell in 1837.

Catastrophes were thought to be the main cause of the changes seen in the record of the rocks and fossils. This record appeared to show that the Earth had suffered occasional gigantic upheavals in what was otherwise a quiet planet.