Double headed eagle

In heraldry and vexillology, the double-headed eagle is a charge associated with the concept of Empire. Most modern uses of the symbol are directly or indirectly associated with its use by the Roman/Byzantine Empire, whose use of it represented the Empire's dominion over the Near East and the West. But the symbol itself is, in fact, much older, and its original meaning is debated among scholars. The eagle by itself has long been a symbol of power and dominion.

The double-headed eagle motif appears to have its ultimate origin in the Ancient Near East, especially in Hittite iconography. It re-appears in the High Middle Ages, from ca. the 10th or 11th century, and was notably used in the Byzantine Empire, but 11th or 12th century representations are also known from Islamic Spain, France and Bulgaria, and from the 13th century onward it becomes more widespread, and is used in the Seljuk Sultanate of Rum, Mamluk Egypt in the Islamic sphere, and in the Holy Roman Empire, Serbia and Russia in the Christian sphere.

Used in the late Byzantine Empire as dynastic emblem of the Palaiologoi, it was adopted during the late medieval to early modern period in the Holy Roman Empire on one hand, and in Orthodox principalities Serbia and Russia on the other, representing an augmentation of the (single-headed) eagle or Aquila associated with the Roman Empire.

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