Matilda's royal seal, showing her enthroned as Empress, became the first English royal seal to depict female power in this iconographic form.
By around mid-1141, with King Stephen in captivity, Matilda began authenticating royal charters and governmental acts using a personal seal that depicted her enthroned in majesty, bearing the title Imperatrix ('Empress'). According to research by The National Archives, this marked the first time that female political power had been visually depicted in this way on an English royal seal — an image asserting sovereign, rather than merely consort, authority.
Seals were a crucial instrument of medieval governance, serving as the visual and legal guarantee of a ruler's authority on official documents. The iconography Matilda chose — enthroned, crowned, holding symbols of rulership — deliberately echoed the imagery used by reigning kings, rather than the more passive, subordinate imagery traditionally used for queens consort standing beside their husbands.
This adoption of royal seal iconography represented a bold visual and political statement of Matilda's claim to rule in her own right, not merely as the wife or mother of a king. Although her practical power collapsed only weeks later following her defeat at Winchester, the seal remains a striking piece of material evidence for how Matilda conceived of and projected her own authority, and it is cited by historians and archivists as an important early instance of female sovereignty being asserted through the visual language of medieval kingship.