Geoffrey V [1110-1151] -- Founder of the Plantagenet dynasty, Duke of Normandy

He married (1128) Matilda, the haughty daughter and designated heir of the English king Henry I. She was the widow of HRE Henry V of Genmany.

When Henry I died (1135), Geoffrey claimed the duchy of Normandy, which he conquered (1141). He ruled as duke until giving it (1150) to his son, Henry (later Henry II).

On the death of Henry I, Matilda's cousin, Stephen of Blois, seized the English crown, despite Henry having designated Matilda as his heir. For the next 19 years the houses of Anjou and Blois fought for control of England and Normandy. Geoffrey concentrated on the duchy while Matilda concentrated on the kingdom.

Ultimately, Stephen was persuaded to acknowledge Geoffrey and Matilda's son, Henry, as heir to England. When Stephen died in 1154, Henry acceded as Henry II.  
 

1144-1150