History of the Mexican Flag
The history of the Mexican Flag is rich and colorful. During the pre-hispanic period, the Aztecan standard bore images of eagles and panthers. Following the conquest, colonial leaders adopted a flag resembling that of Castille, and on August 13, 1530, the Government of Don Alonso de Estrada ordered the first flag parade to commemorate the fall of Tencohtitlan nine years before.
The outbreak of the War of Independence, almost three hundred years later, brought new ideals, new leaders and new flags. Igniting the revolution, Don Miguel Hidalgo unfurled the standard of the Virgen of Guadalupe. During the same struggle, the Generalísimo don Jose María Morelos adopted several different flags, and upon consumation of independence in 1821, added the Flag of the Three Guarantees.
Today's flag has kept the traditional colors red, white and green and bears the national shield in the middle. Mexico has celebrated Flag Day every year since 1937 in a ceremony before the Monument to General don Vicente Guerrero, who was the first military leader to swear allegiance to the flag in Acatempan on 12 March 1821.
The coloration on the Mexican flag represents:
Hope, Fertility of the soil -- Green
Purity -- White
The blood shed during Independence -- Red
According to the legend, the Aztecs in search of their promised land, were told by their god Huitzilopochtli, that when they would find the eagle devouring a serperent on a nopal cactus tree, they were to settle down in that place and found Tenochtitlan, what is today Mexico City.