The alternating white and blue stripes are reported to signify the 9 syllables on the phrase "Eleftheria i thanatos" ("Liberty or Loss of life"), a well known motto through the Greek War of Independence. Through the Kingdom of Greece, a crown was included from the centre with the cross. See https://custom-made-medieval-flag97418.webdesign96.com/33755752/the-definitive-guide-to-medieval-times-flags