Gilbert de Clare, 6th Earl of Hertford, 7th Earl of Gloucester was a powerful English magnate. He was also known as "Red" Gilbert de Clare or "The Red Earl", probably because of his hair colour or fie
Douce Apocalypse, c. 1265–70. The dragon, who is Satan, comes forth again (Rev. 20:7). Among the flags of the host of Satan is that of Gilbert de Clare, Earl of Gloucester, who had opposed Henry III.
1329 seal of William la Zouche, 1st Baron Zouche of Mortimer (died 1337), jure uxoris Lord of Glamorgan, husband of Eleanor de Clare (1292–1337), daughter and eventual heiress of Gilbert de Clare, 6th Earl of Hertford, 7th Earl of Gloucester, Lord of Glamorgan and feudal baron of Gloucester. Inscribed: S(igillum) Will(elm)i La Zouche Domini De Glamorgan ("Seal of William la Zouche, Lord of Glamorgan"). His shield and the caparison of his horse show the Zouche arms