Anian II (Anian Schonaw) was Bishop of the Diocese of St Asaph between 1268 and 1293. His appointment occurred in a period of relative peace, with the area under the authority of Llywelyn ap Gruffydd, and Prince and Bishop on amicable terms. Anian was a party to the settlement between Llywelyn and David Berriw, and also to the compact between Llywelyn and Rhodri (executed at Caernarvon on 12 April 1272). In 1272 he acted as the prince's envoy to Henry III (nearing his end) and was praised by the king for having well performed his task. Llywelyn held hostility towards the new sovereign however, which affected Anian also, and the end of 1273 he wrote to Gregory X making charges against the prince (which, on 7 March 1274, were denied in a joint missive of the Welsh Cistercian abbots assembled at Strata Florida). Later in the year, on 19 Oct., a full assembly of the clergy of the diocese drew up, at the instance of Anian, a statement of the matters at issue between him and Llywelyn, a quarrel which continued during 1275. On 25 May of that year the prince wrote at length to archbishop Kilwardby, complaining of the attacks upon him and offering to accept any reasonable solution. As war became imminent, Anian turned to the king, and on 8 November he obtained from him a confirmation of the ancient liberties of the see, repeated on 20 Jan. 1276 .
On 12 November Anian was present at the council which (at Westminster) declared Llywelyn a rebel, and on his return to St. Asaph, issued a detailed catalogue of grievances against him. During the ensuing struggle he took the king's side, and he appears in the treaty of Conway (November 1277) as one of the royal councillors who escorted the prince to Rhuddlan. The treaty had the effect transferring almost the whole of Anian's diocese from Llywelyn to the control of the Crown. His dealings were now with Edward, and these began quite cordially. He acted as one of the king's justices at Oswestry on 27 Nov. 1277, and (probably in compensation for losses suffered during the late war) about the same time received a grant of arable land in the St. Asaph region (of the annual value of £20, to be divided equally between him and the chapter).
However, the peace did not last, and during a further period of unrest in 1282 there fighting between English and Welsh around Rhuddlan resulted in the burning of the cathedral. Anian, displaying his anger, quitted the diocese and gave no further aid to the campaign (being the only bishop of the province of Canterbury who did not join in the excommunication of the Welsh rebels). Edward's retaliation was to order the confiscation of Anian's goods and, even after the fall of Llywelyn, would not permit his return to his see. The unrest lasted for more than two years, until, at last, the efforts of Archbishop Peckham to restore peace, were successful. In the summer of 1284 Anian consented to pay 500 marks as the price of the King's 'good will', and also withdrew his opposition to the transfer of the Abbey of Conway to the proposed new site at Maenan, with Edward, in return, giving him the advowson of Rhuddlan. On his death in 1293 he was succeeded by Llywelyn de Bromfield.