Division of the field

In heraldry, the field (background) of a shield can be divided into more than one area, or subdivision, of different tinctures, usually following the lines of one of the ordinaries and carrying its name (e.g. a shield divided in the shape of a chevron is said to be parted "per chevron"). Shields may be divided this way for differencing (to avoid conflict with otherwise similar coats of arms) or for purposes of marshalling (combining two or more coats of arms into one), or simply for style. The lines that divide a shield may not always be straight, and there is a system of terminology for describing patterned lines, which is also shared with the heraldic ordinaries. French heraldry takes a different approach in many cases from the one described in this article.

Common partitions of the field are:

(In the above "left" and "right" are from the viewer's perspective, whereas the heraldic terms "sinister" and "dexter" are from the perspective of the person carrying the shield.) Nowadays, however, the 'party' is often omitted, even in 'official' blazons, e.g. in letters patent and extracts of matriculation.

A field cannot be divided per bordure (as, if this did exist, it would be indistinguishable from the bordure), but a bordure can. A bordure can be divided or counter-changed.

Neither can a field (nor any charge) be divided per chief, for similar reasons; though both Canadian and Scottish Public Registers have official records of fields or bordures divided 'per chief'. The earliest such record in the Scottish Public Register is before 1677, "parted per chief azure and gules three skenes argent hefted and pomelled Or Surmounted of as many Woolf-heads couped of the third." and a bordure per chief is shown in the arms of Roy, Canada. A chief is considered a charge in English heraldry and is considered layered atop the field.

Although it is alleged that per chevron enhanced (with the division occurring higher than it normally would) is called mantled in English, this is a term of rare application. When the term rompu is applied to a division of the field, the result will take a number of different forms depending on the manner of division. The arms of Lois Hole show Per chevron rompu Or and Vert, the centre section heightened of two points. (Rompu can also sometimes be applied to "common charges".) A field pily, as in the arms of Baron Marks of Broughton, is similar to a field per fess dancetty, except that the teeth are much more exaggerated.

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