Netherlands

Feb 19, 1937 | Country flag, Merchant flag, Naval flag, Special, State ensign, State flag, War flag |

  Oldest tricolor flag of the...

Turkey

May 29, 1936 | Country flag, Merchant flag, Naval flag, State ensign, State flag, War flag |

Vatican City

Jun 7, 1929 | Country flag, Special, State flag, War flag |

Together with Switzerland the only square flag in the world....

Taiwan (Republic of China)

Jan 1, 1928 | Country flag, Disputed, Naval flag, State ensign, State flag |

...

Alaska

Jul 9, 1927 | State / Province |

...

Liechtenstein 1921-1937

Oct 5, 1921 | Country flag, State flag |

...