This image represents an early form of the byzantine tetragrammatic cross or the symbol preceding it, depicted in traditional colors golden on a red background. According to the historian A. Babuin, the images of flags with crosses quartered with golden discs survive from the 10th century, and a depiction of a flag almost identical to the Palaiologan design is known from the early 13th century. This image can be considered a possible reconstruction and can be used in some articles and templates as a flag or symbol of the Byzantine Empire, but beware, this image is highly speculative and its use should be avoided in infoboxes and articles, where it could be presented as a historical state insignia.
https://commons.wikimedia.org/wiki/File:Golden_Greek_cross_and_discs_of_the_Byzantine_Empire.png
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