Tysilio
Welsh bishop, prince and scholar
Saint Tysilio (also known as/confused with Saint Suliac; Latin: Tysilius, Suliacus; died 640 AD) was a Welsh bishop, prince and scholar.
Sources
The 12th-century poet Cynddelw Brydydd Mawr wrote "An Ode to Tysilio". There is a genealogy of Tysilio in the Bonedd y Saint, and he is mentioned in the 14th-century vita of Saint Beuno.
Although there is no extent vita of Tysilio, apparently in the 15th century some Breton clerics used details from the life of Tysilio to construct a legenda for their own Saint Suliac. Thus, they indirectly preserved some information regarding Tysilio (and also caused some confusion between the two).
"Suliau" has been used an alternate variation for Tysilio and has sometimes led to his being confused with the Cornish saint Sulien.
Life
Tyslio was the second son of the reigning King of Powys, Brochwel Ysgithrog, and his wife Arddun Penasgell, and the maternal nephew of the great Abbot Dunod of Bangor Iscoed. He took part in the affairs of Wales during the distressful period at the opening of the 7th century.
Tysilio probably started his career in Trallwng Llywelyn (Welshpool) and afterwards took up residence in Meifod where he studied under Gwyddfarch.
Around 630, Tysilio moved to an island in the Menai Strait, (now called Ynys Tysilio, where he established a hermitage, and preached throughout Ynys Môn for the next seven years.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Aug 20, 2026. The linked authority identifier is Q1293017. VIAF identifies the subject as 166830904. The Library of Congress control number is nr93007480. 2 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “Tysilio” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.