Compartment (heraldry)

In heraldry, a compartment is a design placed under the shield, usually rocks, a grassy mount (mount vert), or some sort of other landscape upon which the supporters are depicted as standing. Care must be taken to distinguish true compartments from items upon which supporters are merely resting one or more feet, or, sometimes, mere heraldic badges or pure decoration under the shield, and, conversely, care must also be taken in very unusual cases such as the coat of arms of Belize, in which what may be taken to be a crest, the mahogany tree rising above the shield, is really part of the compartment. It is sometimes said to represent the land held by the bearer. As an official part of the blazon it is a comparatively late feature of heraldry, often derived from the need to have different supporters for different families or entities, although sometimes the compartment is treated in the blazon separately from the supporters.

If the compartment is mentioned in the blazon it forms part of the grant and is an integral part of the arms e.g. the current royal arms of the United Kingdom are required to have a compartment with plant badges. If no compartment is specified in the blazon then whether to draw one is at the discretion of the artist. The current arms of the Commonwealth of Australia are usually depicted on a compartment of a wreath of wattle, the national flower. It would be acceptable to omit the wattle or substitute something else as it does not form part of the grant.

The decorative flourish which was often placed by heraldic artists under the feet, hooves or paws of supporters, chiefly in the 19th century, was disparagingly known by some as the "gas bracket," although this term never had any official currency; the only case in which something similar was ever actually mentioned in the blazon was the "arabesque" vert on which the whale supporters of Zaanstad, Noord Holland, the Netherlands, balance. The compartment of the coat of arms of Michigan is similar.

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