Current Flag:
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This flag is a monster. It is based off of a military flag flown by North Dakotans in the Philippine-American war. There isn’t much symbolism I can find here, other than the eagle, which represents the Great Seal of the United States.
My Redesign:
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This flag draws inspiration from the Flag of the Governor of North Dakota. I don’t know what the symbolism of that is, but it looks nice. I would guess that the Fleur-de-lis represents France, as North Dakota was part of New France, and the three stars represent New France, New Spain, and the United States of America, respectively.