Unlike most modern brooches, fibulae were not only decorative; they originally served a practical function: to fasten clothing for both sexes, such as dresses and cloaks.
[3] Lost fibulae, usually fragments, are frequently dug up by amateur coin and relic hunters using metal detectors.
In the 3rd century AD, the hinge was placed in the centre of a long transverse bar, creating the famous crossbow fibula design.
For example, the Asia Minor Decorated Arc Fibula (Blinkenberg Type XII Variation 16) dates to the 5th century BC.
The Romans also used fibulas to fasten the foreskin above the penis, thus hiding the glans, this was done both to show modesty and in the belief that it helped preserve the voice.
A variant that appeared in the 6th century BC had four small spirals with a square, or squarish, cover plate on the middle, the Vierpass type.
In these so-called Italianate fibulae, the bow begins, at the head, with a semi-circular form, but bends at its apex to angle straight down to the foot that was often lengthened and extended.
The latter variants were known as serpentine fibulae.Meanwhile, the 8th and 7th centuries BC saw the introduction of the so-called Phrygian bow fibulae in Asia Minor.
In the same period, the Hand or Arm fibula spread from Cyprus, where it appears to have originated, to Syria, Assyria and Persia.
In this design the bow was bent 90 degrees at the apex giving the fibula a triangular shape when viewed from the side.
The rounded bow fibula underwent several variations and were usually highly decorated with incised or moulded geometric designs.
In one variation, the foot of the fibula that had previously terminated at the end of the arch with a simple catch plate, lengthened significantly.
In another variant, the Schussel type, the ribbon-like bow widened at the head into a rounded arrowhead shape that covered the spring.
The rapid spread of the Roman Empire by the 1st century AD resulted in a tremendous growth in the number and design of fibulae throughout Europe and the Near East.
Bows were cast in more complex forms, hinges appeared alongside bilateral springs and a wide variety of plate designs were introduced.
One of the first fibula designs of the Roman-era began in the La Tène III era, in the late 1st century BC.
Usually quite small, Hod Hill fibulae have a shallow arched bow that appears to be made up of lumpy segments.
The Fantail fibula, which have a short bow that flares into a flat, wide fan-shaped foot, were common in Britain and on the European continent.
A common and widespread design was the Augen (or Eye) fibula, which has a longer bow and a long, flat, wide foot.
The Thracian Anchor type is also called the Illyrian and is found in Pannonia (Hungary), Dacia (Romania) and Serbia.
Kräftig Profilierte fibulae have a wide fan-, or bell-shaped head and a long thin pointy foot.
The most common forms of plate fibula in the 1st century AD were round (disc), diamond, oval and lunula (crescent- or moon-shaped).
In Roman Britain the fibula designs common in the 1st century AD continued to some extent into the second, although usually in more complex variations.
The Knee fibula, a common design in the 2nd century AD, originated in Roman Pannonia (modern Hungary).
The Trident fibula has a rounded arch and long foot and a wide, flat head plate with three points.
[4][5] The crossbow fibula consists of a highly arched semi-circular bow, usually of squarish cross-section, and a long flat foot.
Another variant, dating to the 4th and 5th centuries, the Bugelkopf type, has no transverse bar, or arms at all but retains the round knob at the head.
The ring, or annular, fibula or brooch is extremely hard to date as the design for utilitarian pieces was almost unchanged from the 2nd to the 14th centuries AD.
The penannular brooch, with an incomplete ring and two terminals, originally a common utilitarian clothes fastening, normally of base metal, in Iron Age and Roman Britain developed in the post-Roman period into highly elaborate and decorative marks of status in Ireland and Scotland, made in precious metals and often decorated with gems, and worn by men and women, as well as the clergy as part of their vestments when conducting services.
Ornate Irish examples in the period are usually "pseudo-penannular"; in fact closed rings, but imitating the penannular form.