Bran: Irish, a raven. (Irish Pedigrees; or, The Origin and Stem of the Irish Nation, O'Hart, 1892)

... Brenhin and Bran, in Welsh, are words which have had a currency, in ancient and modern times, with the meaning of "king."... (Celtic Inscriptions on Gaulish & British Coins, Poste, 1861)

(Irish Pedigrees; or, The Origin and Stem of the Irish Nation, O'Hart, 1892)

... The Triads and the prolific Genealogy of Welsh Saints, are the authorities for the existence of a prince Bran.  Bran the Blessed, the son of Llyr Lledaith, and father of Caradwg, is, we are told, one of the three blessed princes of Britain, having brought home the faith of Christ from Rome, where he had been seven years as a hostage for his son Caradwg, whom the Romans put in prison after being betrayed through the enticement, deceit, and plotting of Cartismandua, or by her Welsh name, Avegwydo Foeddog, the daughter of Avarwy, who betrayed Caswallon.  Her act is called by the Triads one of the three secret treasons of Britain...
    Bran stands forth in old Welsh romance as the original importer of the Sanc-greal.  One very old and wild version says that King Bran brought from Ireland a magic vessel, given him by a great black man in Ireland, which healed wounds and raised the dead. 
    In the twelfth century the Sanc-greal had assumed its Christian character, and Bran the Blessed, as the first Christian prince of Britain, was said to have received it from St. Joseph of Arimathea, and guarded it to the end of his life.  No wonder, therefore, that Brittany loved and honoured his name.
    Bran was a Pictish prince, killed in 839, in battle with the Danes, and it is highly probable that St. Birinus, the Keltic apostle of Wessex, was another form of Bran... (History of Christian Names, Yonge, 1884)