Okay, from the Jewett guru on Ancestry.com (James Jewett):
re: Edward's mother: still kind of a mystery. Possible that the Bellyn link is real, however, no connecting records to prove it. I think it is possible William Jewett, possible father of our Edward, was married to sisters. Cicely and Margery, one perhaps died after marriage. William was the Mayor of Chester where the Bellyn sisters were born and parents lived. Edward owned land in a time when only members of the Royal family could, so, logically, there is a connection. Tristan Bellyn was a witness of Edward's will which adds a little more credit. It is also possible that the father of Thomas Jewett was Henry Jewett who was thought to have married Margery Bellyn. Again, records are an issue.
DNA now shows our trail through the Northern part of France which puts us in good company with William the Conquer and his group that came over in 1066. Most of these men can be traced to a place in France, but our male ancestor appears to not be among them.
Note: one such French person was: Henri de Juatt,a Knight of the First Crusade, 1096-1099. This also from the source below but, as Jim states, no supporting documentation.
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A bit more Bellyn/Poole info from this source (in its introduction):
Jewett, Frederic Clarke, [
http://archive.org/details/historygenealogy01jewe History and Genealogy of the Jewetts of America], Volume I, The Grafton Press, New York, 1908. Pgs. xv-xvi.
Following down to a little later date we find in Vol. XVIII. of the "Harlien
Society (English) Reports" : "The arras of Jewett, of Chester, England
—
Argent, on a cross Gules, five fleur-de-lis of the first, in dexter chief a
crescent of the second." " William Jewett, of the Cittie of Chester, alderman
and Justice of Peace, and was maior thearof Anno D'ni 1578, a seconnde
Sonne to Thomas Iwett, of Heyton, in Bradfordc Dale in the Countye of York where Thomas mariede Elizabeth doughter to * * * Shakellton of Myddopp
in Heptonstall within the vicaredge of Holly-fax Com. Ebor' And
mother to the saide William whitch William Iwett mariede Margery doughter
to Robert Bellyn late of the Cittie of Chester which Robert Bellyn married Cicelye
doughter to John Poole seconnde sonne to Sr John Poole in Warral
County of Chester knight.
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So, bottom line, I don't think we can prove or disprove anything ... so far.