Aquila (Roman)

An aquila, or eagle, was a prominent symbol used in ancient Rome, especially as the standard of a Roman legion. A legionary known as an aquilifer, or eagle-bearer, carried this standard. Each legion carried one eagle.

The eagle was extremely important to the Roman military, beyond merely being a symbol of a legion. A lost standard was considered an extremely grave occurrence, and the Roman military often went to great lengths to both protect a standard and to recover it if lost; for example, see the aftermath of the Battle of the Teutoburg Forest, where the Romans spent decades attempting to recover the lost standards of three legions.

No legionary eagles are known to have survived. However, a number of other Roman eagles, either symbolizing imperial rule or used as funeral emblems, have been discovered.

The signa militaria were the Roman military ensigns or standards. The most ancient standard employed by the Romans is said to have been a handful (manipulus) of straw fixed to the top of a spear or pole. Hence the company of soldiers belonging to it was called a maniple. The bundle of hay or fern was soon succeeded by the figures of animals, of which Pliny the Elder (H.N. x.16) enumerates five: the eagle, the wolf, the ox with the man's head, the horse, and the boar. In the second consulship of Gaius Marius (104 BC) the four quadrupeds were laid aside as standards, the eagle (Aquila) alone being retained. It was made of silver, or bronze, with outstretched wings, but was probably of a relatively small size, since a standard-bearer (signifer) under Julius Caesar is said in circumstances of danger to have wrenched the eagle from its staff and concealed it in the folds of his girdle.

...
Wikipedia