BOII (perhaps = “the terrible”), a Celtic people, whose original home was Gallia Transalpina. They were known to the Romans, at least by name, in the time of Plautus, as is shown by the contemptuous reference in the Captivi (888). At an early date they split up into two main groups, one of which made its way into Italy, the other into Germany. Some, however, appear to have stayed behind, since, during the Second Punic War, Magalus, a Boian prince, offered to show Hannibal the way into Italy after he had crossed the Pyrenees (Livy xxi. 29). The first group of immigrants is said to have crossed the Pennine Alps (Great St Bernard) into the valley of the Po. Finding the district already occupied, they proceeded over the river, drove out the Etruscans and Umbrians, and established themselves as far as the Apennines in the modern Romagna. According to Cato (in Pliny, Nat. Hist. iii. 116) they comprised as many as 112 different tribes, and from the remains discovered in the tombs at Hallstatt, La Tène and other places, they appear to have been fairly civilized. Several wars took place between them and the Romans. In 283 they were defeated, together with the Etruscans, at the Vadimonian lake; in 224, after the battle of Telamon in Etruria, they were forced to submit. But they still cherished a hatred of the Romans, and during the Second Punic War (218), irritated by the foundation of the Roman colonies of Cremona and Placentia, they rendered valuable assistance to Hannibal. They continued the struggle against Rome from 201 to 191, when they were finally subdued by P. Cornelius Scipio Nasica, and deprived of nearly half their territory. According to Strabo (v. p. 213) the Boii were driven back across the Alps and settled on the land of their kinsmen, the Taurisci, on the Danube, adjoining Vindelicia and Raetia. Most authorities, however, assume that there had been a settlement of the Boii on the Danube from very early times, in part of the modern Bohemia (anc. Boiohemum, “land of the Boii”). About 60 B.C. some of the Boii migrated to Noricum and Pannonia, when 32,000 of them joined the expedition of the Helvetians into Gaul, and shared their defeat near Bibracte (58). They were subsequently allowed by Caesar to settle in the territory of the Aedui between the Loire and the Allier. Their chief town was Gorgobina (site uncertain). Those who remained on the Danube were exterminated by the Dacian king, Boerebista, and the district they had occupied was afterwards called the “desert of the Boii” (Strabo vii. p. 292). In A.D. 69 a Boian named Mariccus stirred up a fanatical revolt, but was soon defeated and put to death. Some remnants of the Boii are mentioned as dwelling near Bordeaux; but Mommsen inclines to the opinion that the three groups (in Bordeaux, Bohemia and the Po districts) were not really scattered branches of one and the same stock, but that they are instances of a mere similarity of name.
The Boii, as we know them, belonged almost certainly to the Early Iron age. They probably used long iron swords for dealing cutting blows, and from the size of the handles they must have been a race of large men (cf. Polybius ii. 30). For their ethnological affinities and especially their possible connexion with the Homeric Achaeans see W. Ridgeway’s Early Age of Greece (vol. i., 1901).
See L. Contzen, Die Wanderungen der Kelten (Leipzig, 1861); A. Desjardins, Géographie historique de la Gaule romaine, ii. (1876–1893); T. R. Holmes, Caesar’s Conquest of Gaul (1899), pp. 426-428; T. Mommsen, Hist. of Rome, ii. (Eng. trans. 5 vols., 1894), p. 373 note; M. Ihm in Pauly-Wissowa’s Realencyclopädie, iii. pt. 1 (1897); A. Holder, Alt-celtischer Sprachschatz.