Bayonne (; Gascon Baiona ; ; ) is a city and commune in southwestern France at the confluence of the Nive and Adour rivers, in the Pyrénées-Atlantiques department, of which it is a sub-prefecture. It belongs to both vernacular cultural regions of Basque Country and Gascony.
Together with nearby Anglet, Biarritz, Saint-Jean-de-Luz, and several smaller communes, Bayonne forms an urban area with 178,965 inhabitants at the 1999 census, 40,078 of whom lived in the city of Bayonne proper (44,300 as of 2004 estimates).
The communes of Bayonne, Biarritz, and Anglet have joined into an intercommunal entity called the Agglomération Côte Basque-Adour (formerly Communauté d'agglomération de Bayonne-Anglet-Biarritz (BAB) prior to 2010).
In the 3rd century AD, the area was the site of a Roman castrum called Lapurdum, which was a military site, but not a port. In 840 the Vikings appeared before Lapurdum; in 842, Viking chieftain Björn Ironside and his troops launched a large-scale inland offensive and settled outside the city on the river bank. Lapurdum was an oppidum and they needed a port. Bayonne (from Basque ibai, "river") became a key place on the route between the Adour and Ebro rivers, which served as a kind of link between the Atlantic Ocean and the Mediterranean Sea. This commercial route was the main goal of Danish invaders in France. By this route, they could easily reach Muslim-controlled Tortosa, which was the main marketplace in Europe dealing with slaves.
By the 13th century, the city was an important port, with a Gascon and Basque population. As part of Aquitaine, it was ruled by England between 1151 to 1452 and was a key commercial center at the southern end of the English kingdom.
Its importance waned somewhat when the French king, Charles VII, took the city at the end of the Hundred Years' War and the Adour changed course shortly afterwards, leaving Bayonne without its access to the sea. The French, however, realised Bayonne's strategic site near the Spanish border and in 1578 dug a canal to again redirect the river through the city.
Bayonne endured numerous sieges from Plantagenet times until the end of the First French Empire in 1814. In the 17th century, Vauban built large fortifications and the Citadelle in and around the city. These proved crucial in 1813 and 1814 during the siege of Bayonne, when Wellington's army besieged the city in the Napoleonic Wars, only taking it when they used a bridge of ships across the Adour to position artillery around the city.
Bayonne's location close to the border, but also within the Basque Country straddling both France and Spain, gave it an often privileged position in commerce. Basque sailors travelled the world, bringing back products such as cinnamon and riches from piracy and the whaling and cod trades. An armaments industry developed, giving the world the "bayonet". Jewish refugees from the Spanish Inquisition from 1560 brought new trades, most notably chocolate-making, which is still important in Bayonne. Spanish Basques also sought refuge in Bayonne in the 20th century during Francisco Franco's repression, with Petit Bayonne still a centre of Basque nationalism.
By the mid-19th century, Bayonne had declined somewhat with the centralisation of power to Paris and to the new département capital, non-Basque Pau, after the 1789 French Revolution, and with Wellington's bombardment. However, rail links with Paris from 1854 and the growing importance of nearby Biarritz as a tourist centre brought industrialisation and development. Bayonne is now part of 'BAB' (Bayonne-Anglet-Biarritz), a metropolitan area of almost 200,000 people.