The Catalan Countries are those territories where the Catalan language is spoken. They include the Spanish regions of Catalonia, the Balearic Islands, Valencian Community, and parts of Aragon and Murcia (Carche), as well as the Principality of Andorra, the department of Pyrénées-Orientales in France, and the city of Alghero in Sardinia (Italy). It is often used as a sociolinguistic term to describe the cultural-linguistic area where Catalan is spoken. In the context of Catalan nationalism, the term is sometimes used in a more restricted way to refer to just Catalonia, Valencia and the Balearic Islands. The Catalan Countries do not correspond to any present or past political or administrative unit, though most of the area belonged to the Crown of Aragon in the Middle Ages. Parts of Valencia (Spanish) and Catalonia (Occitan) are not Catalan-speaking.

Catalan, known in the Valencian Community and Carche as Valencian, is a Western Romance language. It is the official language of Andorra, and an official language of three autonomous communities in eastern Spain: Catalonia, the Balearic Islands and the Valencian Community, where it is called Valencian. It has semi-official status in the Italian comune of Alghero, and it is spoken in the Pyrénées-Orientales department of France and in two further areas in eastern Spain: the eastern strip of Aragon and the Carche area in the Region of Murcia. The Catalan-speaking territories are often called the Països Catalans or "Catalan Countries".