It is recorded that Nicholas De Mereworth and Iseult Crevequer married in
the reign of King Edward The First (1272-1307) but no date yet found.

Hamo de Crevequer
From Wikipedia, the free encyclopedia.
Hamo de Crevequer (died 1263) was a Norman nobleman who held the office
of Lord Warden of the Cinque Ports.
Gerinun de Holeburn was in 1263 one of a jury of twelve assembled
lawfully to conclude upon an ‘inquisition into how much land ‘Hamo de
Creuker’, (Crevequer) Baron of Chatham, deceased, held of our Lord the
King, at Ledes’ in Kent. (York Cathederal Library).
Hamo de Crevequer took possession of his lands at Brenchley in 1217; he
was succeeded by his grandson Robert. In 1264/5, Robert's lands were
seized by Gilbert de Clare, 3rd Earl of Gloucester. It is recorded that
from April 29, 1230, a market was held each Sunday by Hamo de Crevequer,
until it was ordained by Henry III on June 30, 1233, that the market
formally held in the churchyard should in future be held on de
Crevequer's own land, but on a Saturday.
Hamo de Crevequer acquired property in Folkestone, Kent, England, from
the barony of the family of Abrincis.
His daughter, Iseuld, who was born between 1251-1286, was married to John
de Sandwich. She subsequently married Nicholas Merryweather was born
between 1251-1286 in Lenham, Kent, England, some time during the reign of
King Edward I of England (1272-1307).
On 12 Jun 1285, Edward I inspected a charter of Robert de Crevequer,
granting the Castle of Ledes the fair of Chatham. By 1380 the fair had
become the king’s own right, for his wife.
By 1296 the market at Brenchley was being held by Gilbert de Clare, earl
of Gloucester and Hertford, and in 1312 de Clare claimed that his
ancestors had held the market 'from time out of mind'.
De Clare followed Hamo de Crevequer, some years later as Lord Warden of
the Cinque Ports. (Not currently listed on the Wikipedia list of lord
wardens).
Probable Family History:
A Hamo De Crevequer was born before 1066 in Normandy. Sire "de
Cregrave-Vecœur," (with/at) Driencourt (and/at) Briencort, followed the
Duke in the battle (at Hastings). (Wace)
Also known as Fitz-Hamon, the father of the first Robert de
Cregrave-Vecœur who founded the Priory of Leeds, (Ledes) in Kent, in
1119, and had, by his wife Rohais, three sons, Adam, Elias, and Daniel,
and a daughter named Gunnora.
"He was succeeded by Daniel, who, in the 12th year of Henry II, on
assessment of aid for the marriage of the King's daughter, certified to
the possession of fourteen knights' fees "de veteri feoffemento," and his
son and successor, another Robert, was the father of Hamon", the last of
his line who married to the heiress of Folkestone. (Hasted)
Prince Odo, Earl of Kent, (Half brother to William I) was consecrated and
instituted in 1049 as the Bishop of Bayeux by William, Duke of Normandy.
Born in Normandy about 1032 he fell from grace, and was attained and
imprisonerd at Rouen until the king's death, in 1087. In 1087 Hamo the
Lord of Folkstone was granted the manor of Lenham, seven miles to the
south east of Maidstone, lands then possesed by Mereworth (Odo).
"Hamo the Steward Also called Hamo the Sheriff. Sheriff of Kent; a judge
at Penenden in case between Lanfranc and Odo of Bayeux. Holdings in
Essex, Kent and Surrey."