Bayonne (Basque, baia ona, good bay), a city of S. W. France, department of. Basses-Pyrenees, at the confluence of the Nive with the Adour, 2 1/2 m. from the bay of Biscay, 18 m. from the Spanish frontier, and 113 m. S. S. W. of Bordeaux; pop. in 1866, 26,333. It is separated into three parts, Great and Little Bayonne and the suburb of Pont St. Esprit, which is on the opposite side of the Adour, and is inhabited mainly by Jews, descendants of fugitives from Spain. Bayonne is strongly fortified, has one of the finest arsenals in France, handsome quays and promenades, a mint, a theatre, a seminary, schools of commerce, naval and commercial docks, chamber and tribunal of commerce, distilleries, sugar refineries, and glass works. It has a considerable trade with Spain, and exports timber, tar, corks, hams, chocolate, liqueurs, and cream of tartar. It has a cathedral of the 12th century, and a citadel built by Vauban. Bayonne is supposed to occupy the site of an ancient town named La-purdum. Though it has been besieged many times, it has never been captured, wherefore the inhabitants call it the virgin city.

In the middle ages it was long held by the English with Aquitaine, but was surrendered to Charles VII. in 1451. It was here that the notorious convention between Napoleon and the court of Spain was held in April and May, 1808, in which the emperor by persuasion and threats extorted from Ferdinand VII. the retrocession of the Spanish crown to his father Charles IV., and from the latter (May 5) an abdication in favor of a successor to be chosen by Napoleon. This successor was his brother Joseph.