An aventail (/ˈævənteɪl/)^[1] or camail (/kəˈmeɪl, ˈkæmeɪl/)^[2][3] is a flexible curtain of mail attached to the skull of a helmet that extends to cover at least the neck, but often also the throat and shoulders. Part or all of the face, with spaces to allow vision, could also be covered. Some featured a ventail (a mail flap next to the mouth) which could be folded over the bottom face and vice versa, much in the same manner as a visor.

European history

Early and High Middle Ages

Aventail of chain mail started appearing on Northern European helmets as early as the 6th century, as seen on several Vendel Era helmets, most notably the Valsgärde 8 helmet (580–630 AD)^[4] from Uppsala, Sweden, but also the well preserved Coppergate Helmet (ca. 750–800 AD) from York, England. These early appearances varried greatly in configuration, the Valsgärde 8 helmet featuring a aventail which enclosed the entire lower face, throat and neck, versus the Coppergate Helmet, which combines hanging cheek guards with a aventail for the neck (a configuration likely also used on the similar 7th century Anglo-Saxon Pioneer Helmet).

The enclosed Vendel style aventail came to be the most conventional type going forward into the High Middle Ages. Some configurations fixed the frontal aventail to a spectacle visor (upper face mask) like the Vendel 8 helmet or a nasal guard, notably seen on several Rus' and Kievan Rus' high medieval helmets. Other configurations let the aventail hang loose infront of or under the face like a veil, most likely with an inner liner against chafing or padding against blows. A reason to not connect the frontal chain mail to a spectacle visor or nasal guard might have been to allow for a ventail, a flap of mail which allowed the user to open and close the mail over the mouth for added flexibility. Archeological finds of complete aventails from the early medieval period are however sparse and more than often only a few perforated attachment holes remain.

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  Valsgärde 8 helmet (580–630 AD)^[4] with an enclosed aventail fixed to the visor
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  Coppergate Helmet (ca. 750–800) with a neck aventail combined with cheek guards
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  Yarm helmet (10th century) drawing with a hypothetical enclosed aventail with loose front
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  Rus' nasal helm (11th century) with perforated nose guard for an enclosed aventail
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  Kievan Rus' spectacle helmet (1150–1250) with aventail fixed to the visor

Late Middle Ages

Early aventail were riveted or otherwise fixed directly to the edge of the helmet, however, beginning in the 1320s in Western Europe, a detachable version replaced this type.^[5] The detachable aventail was attached to a leather band, which was in turn attached to the lower border of the helmet by a series of pierced rivets, called vervelles.^[6] Holes in the leather band were passed over the vervelles, and a waxed cord was passed through the holes in the vervelles to secure it.^[7]

Aventails were commonly seen on bascinets in the 14th century and served as a replacement for a complete mail hood (coif). Some aventails were decorated with edging in brass or bronze links (sometimes gilded), or with a zig-zag lower edge (vandyked). By the mid 14th century, the aventail had replaced the mail coif completely. By the dawn of the 15th century, the plate armored neck guard of the Great Bascinet replaced the aventail.^[6]