Flag of Greece At the flag's centre, the royal coat of arms of the new dynasty (Schleswig-Holstein-Sonderburg-Glücksburg) would feature. By a new royal decree of 3 June 1914, the distinguishing flags to be utilised by the various members of the royal family were described. The king's flag was defined as being square in shape and, as in previous flags, featured the coat of arms of the king on a Greek white-cross-on-blue. As the king at the time, Constantine I, was made a field marshal the previous year, the coat of arms on his flag featured a heraldic representation of the Marshal's baton in
Flag of the Greek Orthodox Church of the Byzantine Empire. The double-headed eagle was historically used as an emblem in the late Byzantine period (14th–15th centuries), but not on flags; rather it was embroidered on imperial clothing and accoutrements by both the Palaiologos emperors of the Byzantine Empire and the Grand Komnenos rulers of the Empire of Trebizond, descendants of the Byzantine imperial family of the same name. The actual flag of the Palaiologan-era Byzantine Empire was based on the tetragrammatic cross in gold on a red background. This design also forms the basis for another flag used by the Orthodox Church of Greece, with the