Four entries with the name Rhun.
Rhun
An Arthurian warrior killed at Cwm Cerwyn by the boar Twrch Trwyth. He was the son of Beli Adver.
A Triad calls him one of the Three Red Ravagers of the Island of Britain.
Sources
Culhwch and Olwen | Late 11th century
Triads of the Island of Britain (Welsh ”Triads”) | 11th century to 14th century
Rhun
Ron, Run mab Neton
An Arthurian warrior who was the son of Nwython and the brother of Gwystyl, Llwydeu, and Kinlith.
Sources
Culhwch and Olwen | Late 11th century
Historia Regum Britanniae | Geoffrey of Monmouth, c. 1138
Rhun
An Arthurian warrior who was the son of Maelgwn of Gwynedd.
His experience and wisdom were such that everyone always turned to him for advice.
Source
Breudwyt Rhonabwy | 13th century
Rhun
Paulinus
A son of Urien of Rheged and brother of Owain (Ywaine). He became the Archbishop of York and assumed the name Paulinus.
According to one manuscript, a compilation of history put together by Rhun was one of Nennius’s sources.
The first Bishop of York was Paulinus, who died 10 October 644. He was a Roman missionary whom Pope Gregory I (Gregorio) sent to England. Paulinus arrived 604 with the second missionary group. In 625 he was consecrated as bishop by the Archbishop of Canterbury. Later he was consecrated as Bishop of Rochester, he held the see until his death. He was buried in sacristy of Rochester Cathedral.
Source
Historia Brittonum | Probably Nennius, early 9th century