Thailand

Sep 28, 1917 | Country flag, Merchant flag, State ensign |

...

El Salvador (Motto)

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

...

El Salvador (Variation)

May 17, 1912 | Country flag |

...

El Salvador

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

Flag with the weirdest proportions....

Tibet

Jan 1, 1912 | Unofficial flag |