BOSA (d. 705), bishop of York, was a monk of Hilda's monastery at Streoneshalch (Whitby). When in 678 King Ecgfrith and Archbishop Theodore divided the great northern diocese, presided over by Wilfrid, into three parts, Bosa was made bishop of the Deirans, the people of Yorkshire, and was consecrated by Theodore in the basilica of York. Wilfrid returned to Northumbria in 680, bringing with him a decree from Pope Agatho, commanding that he should be reinstated in his bishopric. Bosa attended the witenagemot that rejected this decree, and he in common with the other intruding bishops, advised the king to imprison Wilfrid. He was expelled from his diocese in 686, and Wilfrid was reinstated by King Ealdfrith. He seems, however, to have regained his see in 691, when the king and Wilfrid quarrelled. At the council of Ouestrefeld, in 702, Wilfrid's chief enemies were the bishops of the north, and Bosa, we may be sure, was prominent among them. lie and Wilfrid were reconciled at the council held on the banks of the Nidd in 705 ; but, though some of Wilfrid's claims were allowed by the council, he was not reinstated in the bishopric of York. Boas, however, died about this time, and was succeeded at York by St. John of Beverley. Bosa. then, as became a disciple of the Abbess Hild, was a member of the national party. He was willing to admit the right of the king and witon to order ecclesiastical affairs, and was jealous of papal interference. His character is highly praised by both Bæda and Alcuin. Acca [q. v.], afterwards bishop of Hexham, was brought up in his household. Boss appears in the calendar as bishop and confessor, his day being 13 Jan.

[Bædæ Hist. Eccl. iv. 12, 23, v. 3, 20; Eddius, Vita Wilfridi, 35, 50, 63, 65, 89, Rolls Ser.; Carmen de Pontiff. &c. Eccl. Ebor. 846; Historians of York, Rolls Ser.; Haddan and Stubbs's Eccl. Documents, iii. 125, 171; Fasti Eboracenses, ed. Raine, 83.]