Josselin I de Thro en Porhoët, vicomte de Bretagne et de Rennes

Oldest surviving, or only known, son of Guethenoc de Porhoet. He is the only one there is definite documentation for. Co-witnessed a charter with his father in1021, which argues that he was as least of an age to understand the importance of doing so (which in turn implies a birth date well before 1020 and requires adjusting the *unknown* birth dates of his parents accordingly).

Vicomte Josselin de Porhoet had three sons with the surname Rohan: Mainguy de Rohan, Jostho de Rohan, and Roger de Rohan. He had a fourth son, the third vicomte de Porhoet, Eudo I de Porhoet (1049-?). There may have been other sons, and perhaps some daughters as well. A charter dated between 1066 and 1082 exists which confirms the donation of property to the abbey of Redon by Josselin, son of the late Guethenoc; it was witnessed by Bishop Mainguy, Roger, Eudo, and "other sons". http://fmg.ac/Projects/MedLands/BRITTANY.htm#_Toc284059618

Eudo was probably the oldest (legitimate) son, since he inherited his father's title and lands. His (half-?)brother Mainguy is said to have become Bishop of Vannes. www.celtic-casimir.com

Cte Josceline I DE PORHOËT Born: Abt 1020, La Trinite Porhoet, Morbihan, Bretagne, France Died: Abt 1074, Guilliers, Morbihan, Bretagne, France

From Wikipedia

Josselin I (of his Latin name Goscelinus or Frank Gauzilin) viscount of Rennes and lord of Porhoët from about 1032 to his death in 1074. He was buried in Redon.

Biography

Son and successor of Guethenoc of Porhoët and his wife Alarun, Josselin gave his name to the new town of Josselin1 built around his castle built by his father2 and his religious foundation.

Under the reign of Alain III of Brittany he is still often mentioned in the acts with the title of "viscount" (of Rennes). He is also the founder around 1050/1060 of the Sainte-Croix priory located near his castle and created in favor of the Abbey of Saint-Sauveur Redon3. He appears in the deed of gift with his sons Mainguy, bishop of Vannes, Roger and Eudon, as well as Perennès, the abbot of Redon.

Union and descent

He will have as descendants4: His successor, Eudon I of Porhoët, Mainguy, Bishop of Vannes, Jostho, Roger.

Notes and references

1. Hervé Abalain, Place names in Brittany, Editions Jean-Paul Gisserot, 2000, p. 74. 2. Augustin Déchaussé (Father Anselme), Genealogical and chronological history of the royal house, vol. 4, Firmin Didot Brothers, 857 p., P. 50 3. André Chédeville Noël-Yves Tonnerre Feudal Brittany XIIth-XIIIth century editions West (France Rennes 1987 (ISBN 9782737300141) p.158 4. Guy-Alexis Lobineau, History of Brittany, vol. 1, widow François Muguet, 1707 (read online [archive]), p. 118

Bibliography Abbé Piédrière, Curate of La Trinité-Porhoët, Essay on the genealogy of the Counts of Porhoët, Bulletin of the Société polymathique du Morbihan, year 1872, pages 234 to 241.

The name(s) of Josselin's wife (or wives, or partner(s)) are unknown.

Vicomte de Bretagne et de Rennes