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. Thereafter the Earldom was more or less bounced back and forth between the de St Liz family and the Kings of Scotland, first being held 1157-65 by Malcolm the Maiden and (1165-74) by his brother William The Lion, King of Scots, then by a Simon de St Liz (grandson of the first Simon and son of the second) from 1174 to 1184.
When the third Simon de St Liz died in 1184 he left no surviving issue and David, younger brother of the Kings of Scots just mentioned, assumed the Earldom from 1185 (on the handing over of it to him by William the Lion) till it was taken away from him in 1215 or 1216 by King John. [Burke's Peerage]
Note: I certainly have descendants of the third Simon de St Liz. Perhaps they are illegitimate, or, maybe the Earldom was taken from the St Liz family by the King of Scots, even if there were legitimate offspring.
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EARLDOM OF NORTHAMPTON (V, 4)
EARLDOM OF HUNTINGDON (VIII)
SIMON DE ST. LIZ III, EARL OF NORTHAMPTON, son and heir of Simon (DE ST. LIZ), EARL OF HUNTINGDON, by Elizabeth DE BEAUMONT, was born about 1138, and at his father's death was a minor in ward to Henry II, remaining so for about 5 years. In I 174 he was recognised as EARL OF HUNTINGDON. He married Alice, daughter and heir of Gilbert (DE GANT), EARL of LINCOLN by Rohese, sister of Roger, EARL OF HERTFORD, and daughter of Richard FITZGILBERT of Clare. He died s.p.s., June 1184 (l), and was buried in St. Andrew's Priory, to which he was a benefactor. At his death the Earldom of Northampton became extinct. His widow was buried at Bridlington. [Complete Peerage VI:645-6, XIV:395, (transcribed by Dave Utzinger)]
(l) His son, Simon IV, mentioned in St. Andrew's Cartulary, dvp. At Michaelmas 1184, the Sheriff rendered account for the rest of the Earl's lands for a small part of the year.
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The following additional information is given by Curt Hofemann in a post-em:
Earl of Huntingdon [Ref: CP VI:643]
minor at father's death, and became ward of step-father, Earl David, until the latter became King of Scotland, when he was given to his great-uncle, Stephen, Count of Aumale [Ref: CP VI:643]
before 1141: reognized as Earl of Northampton [Ref: CP VI:643]
Feb 2 1140/1: fought for Stephen at Lincoln [Ref: CP VI:643]
before 1146: was holding the Honour of Huntingdon [Ref: CP VI:643]
Simon de St. Liz II... succeeded his father... to the Earldom of Northampton only. The Earldom of Huntingdon was by special grace of King Henry I. conveyed to David of Scotland, who on ascending the throne in 1124, transferred it to his only son, Henry, but on Henry's death in 1152, it reverted to Simon. He married Isabel de Beaumont and died about 1154, leaving a son and heir, Simon de St. Liz III. Again the earldoms were divided. Simon III. became the Earl of Northampton, while the Earldom of Huntingdon was given by King Henry II. to Malcolm IV., King of Scotland, the eldest son of Prince Henry, who predeceased his father, and therefore the grandson of King David I. The controversy over the earldom continued, and the King of England, angered by the continual strife and dissension concerning it, ordered the castle demolished. [Ref: McBride2]
Simon de St. Liz, who succeeded to the Earldom of Northampton, but was excluded from that of Huntingdon. He was subsequently, however, restored. [Ref: McBride]
So ... primarliy Earl of Northampton, but later, in 1152, also Huntingdon... Curt
Regards,
Curt
Note: Maybe he was primarily Earl of Northampton, but CP, under Earl of Northampton (for each of the Simon de St. Liz Earls) refers to the Earldom of Huntingdon, where they give a full account. Maybe the Huntingdon Earldom was considered more important or something?