His parentage is specified by Orderic Vitalis. The Chronicæ Sancti Albini records the birth "1113 IX Kal Sep" of "Gaufridus comes".
He succeeded in 1129, when his father abdicated and left for Jerusalem, as GEOFFROY V “le Bel/Plantagenet” Comte d’Anjou. He invaded Normandy in 1137 in support of his wife's claim to succeed her father. He was proclaimed Duke of Normandy 19 Jan 1144, but resigned the dukedom to his eldest son in 1150.
Robert of Torigny records the death "1151 VII Id Sep" of "dux Henricus…pater eius" at "apud Castrum Ledi" and his burial in "civitatis Cinomannicæ…in ecclesia sancti Juliani". The necrology of Angers Cathedral records the death "VII Id Sep 1151" of "Andegavorum comes Gaufridus tertius Martellus gener Henrici…regis Anglorum". 1
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Geoffrey IV, also called Geoffrey Plantagenet, byname Geoffrey The Fair, French Geoffroi Plantagenet, or Geoffroi Le Bel... count of Anjou (1131-51), Maine, and Touraine and ancestor of the Plantagenet kings of England through his marriage, in June 1128, to Matilda, daughter of Henry I of England. On Henry's death (1135), Geoffrey claimed the duchy of Normandy; he finally conquered it in 1144 and ruled there as duke until he gave it to his son Henry (later King Henry II of England) in 1150.
Geoffrey was popular with the Normans, but he had to suppress a rebellion of malcontent Angevin nobles. After a short war with Louis VII of France, Geoffrey signed a treaty (August 1151) by which he surrendered the whole of Norman Vexin (the border area between Normandy and Île-de-France) to Louis. 2
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The Plantagenet family name was originally just a nickname for Geoffrey. He many times wore a sprig with yellow flowers in his hat. The flower was named "genet" or "genistae" in the French of the times--thus his nickname was "Plant-a-Genet". Genet was supposedly a traditional flower of the Anjou family dating back to the time of Fulk, The Great, Count of Anjou 898-941 who was scourged (in order to atone for past sins) with broom twigs of the Genet while on pilgrimage in Jerusalem. Most people of the times had personal nicknames such as "Beauclerc", "Curtmantel", "Longshanks", and "Lackland", but Geoffrey's stuck and eventually (many generations later) became the family name. Geoffrey's immediate descendants were probably not known as the Plantagenet family at the time they lived, it was only later that the Plantagenet family name was applied to all descendants of Geoffrey.