General Notes

It is said that a valet had the audacity to interrupt Sir William at dinner, whereupon seeing his master's anger, fled upstairs; but Sir William pursued him there and in his ungovernable rage, murdered him.
Sir William, in fear and consternation of the deed and its probable consequences, went to London to plead for pardon with the King, for the royal authority was great in those days. Sir William went on his knees before the King and confessed his crime. The King was obdurate and refused to pardon him immediately, but offered to give him a chance. He said he would allow Sir William three days in which to invent a muzzle for a bear; if it proved efficacious, his life would be spared, if not -- well, the bear would provide his punishment!

For three days Sir William was shut up in the tower. At the end of that time he was brought before a bear. The bear was let loose. The prisoner flung his newly invented muzzle over its head and escaped unharmed.

From that time the muzzled bear became the emblem of the Breretons.

(In olden days, bear baiting was a popular form of sport and the bear wore a leather muzzle to prevent it from biting the dog.)

Sir William de Brereton, heir to his father, by deed without date,
  receives from Randle de Torhaunt, later called Thornton, in frank marriage
  with his daughter Margery, all the rents which Thomas de Warin
  held from Peter de Torhaunt, father of the said Randle, in Middlewich
  Hundred. This Randle de Torhaunt must have been Randle le Roter,
  Lord of Thornton, who became possessed of the Manor of Thornton and
  is stated by Collins to have been a son of David le Clerk, Secretary to
  Randle Blundeville, Earl of Chester. Randle assumed the name of le
  Roter, and also of Thornton from his place of residence, and is sometimes
  designated by both. Randle Thornton died before the 28th of
  Henry III, having married Amicia, daughter of Richard Kingsley and his
  wife Joan, daughter and co-heiress of Alexander Sylvester, Lord of
  Stourton and Forester of Wirral, and had a son Ranulph, who died sine
  prole, and 5 daughters: Amicia, Emma, Agnes, Joan and Margaret, of
  whom Amicia, the eldest, was mother of Margery Thornton, wife of Wm.
  Brereton