ANCESTRAL ROOTS, Seventh Edition discusses the line on page 232 (Line number 257) .
The early history of the de la Pole family before
William de la Pole has not been proven.
Dr. Rosemary Horrox in her book on the de la Poles
states "The de la Poles died out in the early sixteen
century, just before the great revival of interest in
geneaology which might have enabled their pedigree to
be traced and preserved. The modern historian of the
family can reach no further back than William of Hull,
in Paston's words, 'a worshipful man grown by fortune
of the world and he was first a merchant and after a
knight and after he was made banneret'.
William de la Pole's wife Katherine also presents a
problem. Frost and Harvey describe Katherine as a
sister of Sir John de Norwich (d. 1362) Earlier writers
make her the daughter. However no sources are given.
William and Katherine had three daughters, Katherine,
Blanche and Margaret. All three were still unmarried
in 1339, when the king promised to provide them with
suitable husbands. By May 1340 Katherine had married
Constantine, the son of Adam de Clifton. The second
daughter, Blanche, married Richard lord Scrope of
Bolton. Margaret, the third daughter, married Robert
Neville of Hornby. This marriage probably took place
around 1362. Dr. Horrox stated "Robert's father,
Robert senior, was then heavily in debt to William,
and had been imprisoned in the Fleet for non-payment of
two thousand pounds. Michael de la Pole obtained his
release in May claiming that the money had been repaid.
This seems unlikely; three days later Robert senior took out
another bond promising repayment of the two thousand
pounds."
The founder of this family, which eventually attained such an exalted station, was William de la Pole, an opulent merchant at Kingston-upon-Hull, who left two sons, William and Richard. [Sir Bernard Burke, Dormant, Abeyant, Forfeited, and Extinct Peerages, Burke's Peerage, Ltd., London, 1883, p. 440, Pole, Barons de la Pole, Earls of Suffolk, &c.]