An ornamented band worn around the brow of a man or woman, sometimes a a badge of sovereignty.
Such pieces were made from ancient times of metal, often gold, in the form of a wreath or sometimes decorated with gemstones, pearls, and other ornaments. They were usually held in place by a long hair pin. Many worn by women had attached long heavy pendent ornaments extending down over the ears and to the shoulders, and sometimes also rings or tassels suspended over the forehead and temples.
Diadems, from simple forms to those lavishly decorated, were worn by the Egyptian pharaohs and their wives. Greek examples varied from simple gold or silver bands to those decorated with repoussé or stamped rosettes or other motifs (including the Heracles Knot), and later with filigree work and granulated gold. Roman diadems developed from wreaths of leaves to head-dresses anticipating the form of a crown.
In western Europe during the Middle Ages the form was that of a chaplet and later of a band of hinged plaques with enamelled and jewelled decoration. In later centuries in France and England the form approached the semi-secular and was profusely ornamented with gemstones. More recently examples were made in Art Nouveau style.
The wearing of a diadem has not been confined to royalty or the nobility; ladies of wealth or fashion have worn them on important social occasions.