The nasal helm is a design of helm that was popular in the late Dark Ages through to the Early Medieval period. The nasal helm was a form of helm with a domed or raised center, usually formed around a basic skull-cap design, with a single protruding strip that extended down over the nose to provide additional facial protection. The helm appeared throughout Europe late in the 9th century, and became the predominant form of head protection. The helm was slowly replaced across the 13th century by helms that provided more facial protection, and although the nasal helm lost popularity amongst the higher classes of knights and men-at-arms, they were still seen amongst archers to whom a wide field of vision was crucial.