The County of Foix (French pronunciation: [fwa]) was an independent medieval fief in southern France, and later a province of France, whose territory corresponded roughly the eastern part of the modern département of Ariège (the western part of Ariège being Couserans).

During the Middle Ages, the county of Foix was ruled by the counts of Foix, whose castle overlooks the town of Foix. In 1290 the counts of Foix acquired the viscountcy Béarn, which became the center of their domain, and from that time on the counts of Foix rarely resided in the county of Foix, preferring the richer and more verdant Béarn.

The county of Foix was an independent fief of the kingdom of France and consisted of an agglomeration of small holdings ruled by lords, who, though subordinate to the counts of Foix, had some voice in the government of the county.

The provincial-states of the county, which can be traced back to the 14th century, consisted of three orders and possessed considerable power and energy. In the 17th and 18th centuries Foix formed one of the thirty-three gouvernements, or military areas, of France and kept its provincial-states until the French Revolution. In 1790 it was joined with Couserans to form the département of Ariège.

Coordinates: 42°57′59″N 1°36′28″E / 42.9664°N 1.6078°E / 42.9664; 1.6078

Foix (French pronunciation: [fwa]; Occitan: Fois [ˈfujs, ˈfujʃ]; Catalan: Foix [ˈfoʃ]) is a commune, the capital of the Ariège department in southwestern France. It is the least populous administrative centre of a department in all of France, although it is only very slightly smaller than Privas. It lies south of Toulouse, close to the border with Spain and Andorra.

The town of Foix probably owes its origin to an oratory founded by Charlemagne, which afterwards became the Abbey of Saint Volusianus in 849. The current area was preceded by the County of Foix.

The coat of arms used by the commune has the blazon Or, three pallets gules. This is replicated on the flag, and in the arms of the département. It originates from the arms of the Counts of Foix, and, as such, dates back into medieval times. It bears a resemblance to the coat of arms of Aragon, both featuring in the coat of arms of Andorra.

Foix was the birthplace of Charles de Freycinet (1828–1923), statesman and prime minister.