Iceland (State flag)

Jan 1, 1919 | Naval flag, State ensign, State flag, War flag |

...

Azerbaijan

Nov 9, 1918 | Country flag, Merchant flag, Naval flag, State ensign, State flag, War flag |

El Salvador (Motto)

May 17, 1912 | Merchant flag, State ensign, State flag, War flag |

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El Salvador

May 17, 1912 | Naval flag, Special, State flag, War flag |

Flag with the weirdest proportions....

Portugal (National colours)

Jun 30, 1911 | War flag |

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Sweden (Naval ensign)

Jun 22, 1906 | Naval flag, War flag |

...