Sulien was an 11th century Bishop of St David's

Bishop of St David's

The Bishop of St David's is the ordinary of the Church in Wales Diocese of St David's.The succession of bishops stretches back to Saint David who in the 6th century established his seat in what is today the city of St David's in Pembrokeshire, founding St David's Cathedral. The current Bishop of St...

, for two periods (1073-1078 and 1079/80-1085/6). He died about 1090/1.

Sulien is closely associated with the class church at Llanbadarn Fawr

Llanbadarn Fawr

Llanbadarn Fawr is an urbanised village and community in Ceredigion, Wales. It is located on the outskirts of Aberystwyth situated next to Penparcau and Southgate. It forms the eastern part of the continually built-up area of Aberystwyth...

 near Aberystwyth

Aberystwyth

Aberystwyth is a historic market town, administrative centre and holiday resort within Ceredigion, Wales. Often colloquially known as Aber, it is located at the confluence of the rivers Ystwyth and Rheidol....

 where it appears that he took refuge when St David's

St David's

St Davids , is a city and community in Pembrokeshire, Wales. Lying on the River Alun on St David's Peninsula, it is Britain's smallest city in terms of both size and population, the final resting place of Saint David, the country's patron saint, and the de facto ecclesiastical capital of...

 was at times exposed to Viking

Viking

The term Viking is customarily used to refer to the Norse explorers, warriors, merchants, and pirates who raided, traded, explored and settled in wide areas of Europe, Asia and the North Atlantic islands from the late 8th to the mid-11th century.These Norsemen used their famed longships to...

 incursions. Llanbadarn enjoyed a reputation for scholarship. One of his sons, Rhigyfarch

Rhigyfarch

Rhigyfarch , eldest son of Sulien, whom he may have succeeded in 1091 as Bishop of St David's, was the author of the standard Life of Saint David. The original text was written in Latin but was translated into Welsh later in the Middle Ages as Buchedd Dewi and did much to enhance the cult status of...

 was the author of a 'Life of Saint David

Saint David

Saint David was a Welsh Bishop during the 6th century; he was later regarded as a saint and as the patron saint of Wales. David was a native of Wales, and a relatively large amount of information is known about his life. However, his birth date is still uncertain, as suggestions range from 462 to...

'.