Gaston III, Count of Foix

Gaston was born either in Orthez or Foix, the eldest son of Gaston II/IX (1308–1343). As the lord's eldest son, he was given the name, Gaston. He later adopted Fébus as a nickname. In its classic spelling, Phoebus, it is one of the names of the sun-god, Apollo, and is apt because of Gaston Fébus's golden hair. His native language was Gascon (a dialect of Occitan), but he was also fluent in French. He wrote a treatise on hunting in French, and an Occitan song, Se Canta, has been ascribed to him. One contemporary chronicler, Jean Froissart, records that he "very willingly spoke to me not in his native Gascon but in proper and elegant French".

Béarn had passed to the county of Foix in 1290. Fébus paid homage to the French king for his own county, but starting in 1347 he refused to give homage for Béarn, which he claimed as an independent fief, with its chief seat his stronghold at Pau, a site that had been fortified by the 11th century, which was later made the official capital of Béarn in 1464.

He was succeeded as count of Foix by Mathieu of Foix-Castelbon.

The House of Béarn-Foix was engaged in a long running feud with the House of Armagnac. In 1362, a battle was fought between the two noble houses at Launac. Fébus was victorious and succeeded in capturing his chief rivals, whom he ransomed for a vast fortune of at least 600,000 florins. This money was stored in the Moncade tower in Orthez, where Fébus also created a gallery of portraits and military trophies to commemorate the event.

Jean Froissart and Espaing de Lyon on their way; Gaston Fébus receiving them.

In late 1388, the chronicler, Jean Froissart, visited the County of Foix and recorded the splendour of Fébus' court at Orthez. He noted that Fébus describes the three "special delights" of his life as "arms, love and hunting".

Fébus was one of the greatest huntsmen of his day, and hunted his entire life – he died of a stroke while washing his hands after returning from a bear hunt. His Livre de chasse (Book of the Hunt) was written between 1387–1389 and dedicated to Philip the Bold, Duke of Burgundy. Recorded in the book are different stages of hunting different animals, as well as describing animal behavior, offering advice to less well-off gentry about how to enjoy hunting without bankrupting themselves, and is even sympathetic to the peasant poacher because he too has the hunting instinct. It is the classic treatise on Medieval hunting, and was described by scholar, Hannele Klemettilä, as "one of the most influential texts of its era". Some forty-four 15th and 16th century illuminated manuscripts survive, the most famous being that held by the Bibliothèque nationale de France, which has exquisite miniatures, illustrating the hunt.

Fébus married Agnès of Navarre (1334–1396), daughter of Joan II of Navarre and Philip III of Navarre in 1348. They had a son:

• Gaston (1361-1382), married Béatrice d'Armagnac (1362-1410), daughter of John II of Armagnac.

He was also the father of four illegitimate children:

• Garcia de Béarn, viscount of Ossau, husband of Anne de Lavedan;
• Peranudet de Béarn, died in childhood;
• Bernal de Foix died about 1381, first count of Medinaceli by his marriage to Isabel de la Cerda, lady of Huelva, Gibraleón and of Puerto de Santa María, the forefather of the dukes of Medinaceli;
• Jean de Béarn, also called Yvain de Lescar, was Fébus' favourite son, dying on 30 January 1393 without issue, of burns accidentally caused at the Bal des ardents.

Gaston III outside the Château de Pau.

As Jean Froissart records, Fébus was betrayed by his son who also bore the dynastic name, Gaston, and who tried to kill his father using poison given to him by Charles II of Navarre. Fébus caught his son in the act and imprisoned him. In a subsequent violent quarrel, Fébus stabbed his son, who died.

With Gaston's death, Fébus had no legitimate heir. In 1393, in Paris at a masquerade given by the Queen of France, Isabeau of Bavaria, one of Gaston Fébus's four recorded illegitimate sons, Yvain de Foix, was burned to death when his costume, along with the costumes of four others, caught fire from a torch at the Bal des Ardents.