What does the Mexican snake mean?

The Mexican flag has a vertical tricolor of green, white, and red with the national coat of arms (The coat of arms depicts a Mexican golden eagle perched on a prickly pear cactus devouring a snake.). The Coat of Arms represents an old Mexican legend where the Aztecs where supposed to settle on a land "where an eagle landed on a prickly-pear cactus, eating a snake... " When they found a eagle on top of the cactus, they settled there and named it Tenochtitlan, where it is now present-day Mexico City

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