The Naval Ensign of Greece between 1858 and 1862 as specified in a decree dated 28 August 1858, signed by Queen Amalia on behalf of King Otto. The decree (which can be found here) replaced the older decree dated 3 June 1833 (which can be found here). The flag remained in use until King Otto was overthrown and the shield was removed. The flag was also used as the rank flag of the Minister of Naval Affairs.
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Philly boy92