A cap of maintenance, known in heraldic language as a chapeau gules turned up ermine, is a ceremonial cap of crimsonvelvet lined with ermine, which is worn or carried by certain persons as a sign of nobility or special honour. It is worn with the high part to the fore, the tapering tail behind. It may substitute for the torse in the heraldic achievement of a person of special honour granted the privilege by the monarch. It thus appears in such cases on top of the helm and below the crest. It does not, however, feature in the present royal coat of arms of the United Kingdom, which shows the royal crest upon the royal crown, itself upon the royal helmet.
Origins
The origin of this symbol of dignity is obscure. One might speculate that the origin relates to the Old French verb maintenir – "to hold" or "to keep". A purpose of the cap was to keep a crown or coronet secure on the head, thus its function was simply to "maintain" the coronet in place. The granting of the cap as an honour might refer specifically to the red velvet and/or ermine trim, distinct from a simpler design of cap.
In more general terms, the velvet and ermine lining of a crown is itself sometimes called a 'cap of maintenance', and is technically a separate item from the crown itself. It may have had a purely practical origin being used to help a crown fit more firmly or to protect the head from bare metal on the crown. As peers' coronets are displayed affronté, or facing forward, the only visible parts are the front of the ermine trim and the velvet top - the ermine tails would be invisible.
Confusion with 'Muscovy hat'
A number of English cities and towns refer to the use of a 'cap of maintenance' as worn by a ceremonial officer, most usually a swordbearer. These are based most often on a design worn by the swordbearer of the Lord Mayor of the City of London. However, this item is called by the City of London authorities a "Muscovy hat" and is a historic reference to the mediaeval trade with the Baltic. The Muscovy hat served as the crest of the City of London until replaced in the nineteenth century by the present crest of A dragon's wing charged with the Cross of St George. The confusion as to nomenclature stems from references in early borough charters granting the right to the use of a ceremonial sword which often mentioned in addition the right to a cap of maintenance. However, this was intended to mean that in civic processions a cap of maintenance should be carried along with the sword, signifying that the mayor was the sovereign's representative. The correct form of use can be seen at the State Opening of Parliament, where it is carried alongside the Sword of State in front of the monarch. It would be quite improper for a commoner to actually wear it.
Variants
In many English towns where the privilege of a sword was granted by the Crown the swordbearer wears a variant of the City of London Muscovy Hat, although some wear other sorts of eccentric headgear which they mistakenly also call a "cap of maintenance". However, the 'grant' is a grant of arms and a heraldic charge rather than an actual object.
The City of York claims to possess an original medieval cap of maintenance, which is kept and displayed in the Mansion House; whatever its origin, it is in fact a "Bycocket" or "Robin Hood" style of cap with ermine trimmings forming into a split peak at the back and was copied from an heraldic drawing and not from a genuine cap of maintenance. Caps of this style are still worn by the York Swordbearers. The City of York claims the grant of a cap of maintenance from the YorkistKing Richard III and incorporates this into its coat of arms as a quasi-crest but reverses it so that the tail or peak faces to dexter, thus further compounding the confusion.
