Flag of Portugal green was harder to come up with, given that it was not a traditional colour of the Portuguese flag's history. Eventually, it was justified on the grounds that, during the 1891 insurrection, this was the colour present on the revolutionary flag that "sparked the redeeming lightning" of republicanism. Finally, white (on the shield) represented "a beautiful and fraternal colour, into which all other colours merge themselves, colour of simplicity, of harmony and peace", adding that "it is this same colour that, charged with enthusiasm and faith by the red cross of Christ, marks the Discoveries epic cycle". The Manueline armillary
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