An insignia () is a sign or mark distinguishing a group, grade, rank, or function. It can be a symbol of personal power or that of an official group or governing body.
An insignia, which is typically made of metal or fabric, is a standalone symbol of a particular or general authority. Together, insignias form a decoration with the different elements of a rank, grade, or dignity.
There are many types of insignia, including civil and military decorations, crowns, emblems, and coats of arms.
Singular/plural
"Insignia" can be used either as a plurale tantum word, i.e. unchanged for both singular and plural, or it can take the plural form "insignias", both equally valid options. The singular "insigne" is rarely used.
History
The use of insignias predates history, both for personal and group (especially military) use. When the insignia was meant to be seen, it was placed at top of a pole or the head of a spear. The Persians used a golden eagle as an insignia, the Assyrians a dove, and the Armenians a lion. The eagle came to serve a more important function as the , the insignia of the Roman legions, around 100 years BCE.
At the earliest times, military insignias were very simple. Tree branches, mauled birds, heads of beasts, or a handful of dry grass, were placed on top of a pole or long stick, so that the combatants could recognize themselves in the fight, or to signpost a meeting place in retreat or defeat. But as the arts of war were refined, sturdier and brighter insignias were designed, and everyone wanted theirs to use characteristic symbols.
Among the Jews, each of the twelve Tribes of Israel had an insignia of a distinctive colour, on which was a figure or symbol that designated the tribe, according to the Blessing of Jacob. Scripture mentions the lion as the symbol of the Tribe of Judah, the ship that of the Tribe of Zebulun, the stars and firmament that of the Tribe of Issachar, and so on.
Idolatrous peoples had images of their gods or symbols of their princes on their insignias. The Egyptians chose the parrot and the crocodile, among others; the Assyrians and Babylonians had doves, as Jeremiah records in chapters XXV and XLVI of his prophecies; because the name "Semiramis", originally "Chemirmor", means "dove".
Ancient Greece
In Heroic times, a shield, helmet, or cuirass on a spearhead were the military insignias of the Greeks. Nevertheless, Homer records that at the Siege of Troy Agamemnon used a purple cloth to mark the meeting-point for his troops.
Little by little, insignias were used on swords and shields. The Athenians had Athena, the olive tree and the owl. The Corinthians adopted a winged-horse, the Thebans a sphinx, the Messinians and Laconians used the initial letter of their name.
Persia
The principal insignia of the Persians was a golden eagle on the end of a pike, placed on a wagon guarded by two of the most distinguished officers. Xenophon assumes that this insignia was used by all the kings of Persia.
Among the ancient armies, sometimes raising a mantle of purple (or any other color) was all that was needed to make an announcement or give the order to attack.
Ancient Rome
At first, the Romans had nothing more than a handful of hay as an insignia, placed at the top of a pole like most others. Over time they took the figures of a wolf, a horse, a boar, and a minotaur until, according to Pliny the Elder, in the second year of his consulate Gaius Marius replaced them all with the eagle, which became the standard insignia for the legions. Each legion, or at least the first, carried a silver eagle with wings extended, on a sculptural base and placed at the top of a pike. The eagle was entrusted to the centurions of the Triarii.
In the age of the Emperors, the armies were often identified by a silver hand with an open palm (manus), known as the Signum manipuli, as a symbol of loyalty. The insignia was carried by an officer called the . Many examples are seen on Trajan's Column, for which the preliminary plans had it topped with a bird, probably an eagle.
Monuments surviving from antiquity usually are adorned with the insignia of crowns and small shields called , on which probably would be portraits of gods or Roman heroes, with other emblems representing each legion. Some battlements are adorned with insignias as trophies of war.
When Germanicus died, many blamed Piso and the legions removed all mention of him from their insignia.