on the history of the Earldom of Huntingdon:
After Earl Simon's [Matilda's 1st husband] death, his Widow married David I of Scotland, who consequently became Earl of Huntingdon too, keeping the Earldom even after he succeeded his brother as King of Scots. He sided with the Empress Maud against Stephen I but came to terms with the latter and made the Earldom over to his son Henry. Henry swore fealty to Stephen but subsequently fought against him under the Scottish banner, which may account for Simon de St Liz's son, another Simon, being recognized as Earl of Huntingdon before Henry's death in 1152. [Burke's Peerage]
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EARLDOM OF NORTHAMPTON (IV, 3)
EARLDOM OF HUNTINGDON (V)
SIMON DE ST. LIZ II, son of Simon DE ST. LIZ, EARL OF HUNTINGDON, by Maud, daughter of Waltheof, EARL OF HUNTINGDON, was a minor at his father's death, and became a ward of his stepfather, Earl David, until the latter became King of Scotland, when he was given to his great-uncle Stephen, Count of Aumale. If he was still under-age in he must have been born later than 1103. He became as strenuous an adherent of Stephen in the civil war as King David and Earl Henry were of the Empress, and before 1141 he had been recognised as Earl of Northampton. He fought for Stephen at Lincoln, 2 February 1140/1, and before 1146 was holding the Honour of Huntingdon, and probably was recogniscd as EARL OF HUNTINGDON also, thus regaining his full inheritance. He founded the Abbey of Sawtrey in Hunts in 1146 or 1147, as Simon, Earl of Northampton, his son Simon witnessing the charter and the Nunncry of St. Mary dc la Prc, ncar Northampton, also in the reign of Stephen, who confirmcd the grant. He also gave charters to St. Andrcw's, Northampton, in one of which he names his wife Elizabeth and his son Simon, and to another his brother Simon was a witness.
He married Isabel or Elizabeth, daughter of Robert, EARL OF LEICESTER, by Amice, daughter of Ralph de Gael II, Seigneur of Gael and Montfort-sur-Meu. He died August 1153, and was buried at St. Andrew's.[k] His widow married Gervase PAYNELL. [Complete Peerage VI:643, XIV:395, (transcribed by Dave Utzinger)]
[k] Robert, Earl of Gloucester, said of him that his acts never reached beyond speeches nor his gifts beyond promises (Henry of Huntingdon, p. 270). The historian's own description of him is "Full of all things unlawful and unbecoming." But these aspersions on his character are disproved by his life. His son Simon ultimately succeeded to the Earldom. He had three daughters, Amice or Amy and Hawise, who remained wards of the King for 5 years, and Isabel, who m. William Maudit, camerarius of Hanslope.