The Highland Clearances (, the "eviction of the Gael") was the forced displacement during the 18th and 19th centuries of a significant number of people from traditional land tenancies in the Scottish Highlands, where they had practised small-scale agriculture. It resulted from enclosures of common lands and a change from farming to sheep raising, an agricultural revolution largely carried out by hereditary aristocratic landowners. The Clearances were a complex series of events occurring over a period of more than a hundred years. A Highland Clearance has been defined as "an enforced simultaneous eviction of all families living in a given area such as an entire glen".