Saint Issel

{{Use dmy dates|date=April 2022}}

{{Infobox saint

| name = St Issel

| image = St Issells church, Saundersfoot (geograph 2607213).jpg

| imagesize = 300px

| alt =

| caption = St Issell's church, Saundersfoot

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| birth_date = {{circa|6th Century AD}}

| birth_place = Kingdom of Dyfed

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| venerated_in = {{flagicon|Wales}} Celtic Christianity Orthodox Christianity

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| tradition= Celtic Rite

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Saint Issel or Issell ({{langx|cy|Eussyllt}} or Usyllt) was a 6th-century Welsh saint in Celtic Christianity. He lived in the Kingdom of Dyfed and is principally notable as being the father of Saint Teilo.

His name appears in many forms in surviving texts, but seems to have been derived from the Latin name Auxilius.

The Book of Llandaff gives his wife as Guenhaf daughter of Liuonui. He was the father of Saint Teilo and the Anauved who married King Budig of Armorica and bore three saints.{{cite book|last=Baring-Gould|first= Sabine & al.|title=The Lives of the British Saints|volume= 4|url=https://books.google.com/books?id=0jLjYgygkB0C&PA348 |page= 348 f|publisher= Kessinger Publishing|year= 2005}} The oldest genealogies present him as also the father of Saint Cynllo.{{cite web|url=http://santiebeati.it/dettaglio/94160 |last=Alonso|first=Justo Fernandez|title=San Cynllo: Santi e Beati |year= 2008}}

He is the patron saint of the parish church at Saundersfoot ({{langx|owl|Llanussyllt}}) but probably not the patron of Haroldston St Issells which was probably corrupted from an original dedication to his grandson Saint Ismael.