Guarine de Meer, a member of the House of Lorraine, in France, was among the first persons of note to whom William, the Conqueror, committed the defense of the Marches toward Wales. (In the 8th century the word marche (French) meant a boundary between two countries or districts, and the earliest Mark or March districts were tracts of land on the border of the Carolingian Empire. Wherever Charlemagne pushed forward the frontiers of the Frankish realm he established Mark districts, and the oversight of these was entrusted to special officers called margraves. In England in the same connection the plural Marches was the form commonly adopted, and soon after the Norman Conquest the disturbed districts on the border of Wales began to be known as the Welsh Marches. Lands therein were granted to powerful nobles on condition that they undertook the defense of the neighboring counties of England. The Mortimers were created Earls of March from this term.) Guarine de Meer received custody of Adderbury, County Salop, and Alestoun, County Gloucester, of which former county Guarine was sheriff in the year 1083, and he was at that time one of the chief advisors and councillors of Roger de Montgomery, Earl of Shrewsbury. Of this Guarine it is stated that, having heard that William, a valiant knight, sister's son to Pain Peverell, Lord of Whittington, in Shropshire, had two daughters, one of whom named Mallet had resolved to marry none but a knight of great prowess; and that her father had appointed a meeting of noble young, at Peverel's Place on the Pike, from which she was to select the most gallant; Guarine came hither; when entering the lists with a son of the King of Scotland, and with a Baron of Burgundy, he vanquished them both, and won the fair prize with the lordship of Whittington, which descended to later FitzWarins for several hundred years. At this place he subsequently took up his abode, and founded the Abbey of Adderbury.
(Kin of Mellcene Thurman Smith, page 484)
Warin de Metz married the Peverel heiress, Melette, and thus gains the lordship of Whittington.
(Fouke le Fitz Waryn, Edited by Stephen Knight and Thomas H. Ohlgren, Originally Published in Robin Hood and Other Outlaw Tales, Kalamazoo, Michigan: Medieval Institute Publications)