The coat of arms, instead, became more and more popular and slowly but steadily pushed the equestrian motif off great seals. By the fifteenth century the standard aristocratic seal was one sided and showed its bearer’s coat of arms.⁶² The large armorial seal contained no visual element referring to a particular layer of rank except, of course, for the rather large group of those having the right to bear arms. However, nothing evoked affiliation to a specific aristocratic rank such as earl or baron. Instead, as stated above, it fully focused on its bearer, his family and his (claimed) lordship(s). This was also the main concern of the small armorial seals. Yet here, during the reign of Edward III, we see the introduction of an element that was used as a symbol of a specific rank: the cap of estate. Edward himself seems to have been responsible for its first use on a seal. On the reverse of his fifth (1340–1347) and sixth seals (1340–1360) a mounted knight was depicted wearing a helmet surrounded by a cap decorated with the royal crest. William St John Hope has suggested that this cap referred to his dignity as duke of Normandy and Aquitaine.⁶³ This may have been the case, but the evidence is not entirely conclusive and so some caution is advisable. The legend of his second seal (1327–1336) provided, inter alia, the title of the duke of Aquitaine, but displayed no cap. The legend found on both the fifth and sixth seals named Edward as king of France, king of England and lord of Ireland, but did not refer to any ducal dignity. One can argue that this was precisely the reason for the introduction of the cap: it communicated the ducal dignities not mentioned in the legend due, perhaps, to the lack of space resulting from the introduction of the title of king of France. When after the treaty of Brétigny in 1360, Edward had yet again cut another seal (used until his death in 1377) the title of French king was dropped. The space that had thus become available was filled once again with the title of duke of Aquitaine. The cap, however, remained part of the design on the reverse of the seal. On his eighth seal, finally, extant from 1372, the title of duke of Aquitaine was again dropped in favour of the title of king of France.⁶⁴ Whatever the reasons for the adoption of the motif of a cap had been, it was quickly adopted by the king’s sons. The king’s first born son and first English duke ever, Edward, displayed a cap on his seals, first on a number of his smaller armorial seals, then also from 1362 on his great seal portraying him as prince of Aquitaine and prince of Wales.⁶⁵ The cap may well have referred to the duchy of Cornwall which he had held since 1337. No doubt exists about the causal relationship between the ducal dignity and the cap on the seal in the case of Henry of Lancaster. When in 1351 Henry was created duke he changed his small armorial seal. The new one displayed a cap of estate above his shield (Fig. 4.3).⁶⁶ The royal sons followed suit in the ensuing decades: Lionel as duke of Clarence and John of Gaunt as duke of Lancaster in 1362,⁶⁷ their brothers Edmund as duke of York and Thomas as duke of Gloucester in 1385.⁶⁸ In 1362, the cap also became part of the investiture ritual of a duke. The dukes had previously been invested like earls, i.e. by being girded with the sword, but now Edward III set them visually apart from the earls. He invested his son by placing a cap of fur and a golden coronet on his head. They were the signs of his new ducal dignity.⁶⁹ In contrast to the earls, the dukes therefore had a common symbol on their small seals that referred to their specific rank. Yet, the cap did not retain its ducal exclusivity on seals. Soon it was also adopted by far lesser men. In 1415, Gilbert Talbot, lord of Archenfield and Blackmere in Hamsphire, used an armorial seal which displayed above the shield what looks like a cap of estate.⁷⁰ This shows once more the lack of official regulation concerning the design of seals. Aristocrats were relatively free in their choices.⁷¹