The flag has a white colors, representing peace. The three crosses (known as crosses pattées in heraldry) represent the nao Santa María and the caravels Pinta and Niña, the three ships ceded to Christopher Columbus in the discovery of American continent, as well as the Christianity. They are purple, according to the author of the flag, the Uruguayan army captain Ángel Camblor, in reference to the lion of the kingdom of Leon, later annexed to the Crown of Castile, where the Spanish idiom was developed. The sun represents the Inca sun-god Inti, associated in some countries with the May Sun.
This flag is used in Spanish-speaking Latin America, Hispanic communities in North America, and in Philippines, as an ethnic flag of ethnic people. Its use is most commonly flown in Columbus Day. In those occasions, it's also known as "bandera de la raza" (i.e. "flag of the race").
Moreover, it's officially regarded, in all countries of the continent, as the "flag of the Americas" i.e. as a Pan-American flag independently of ethnic identity, since the seventh assembly of Pan-American Conference, occurred in 1933.
As I said, I think this flag should me much more popular, specially in its use as a Pan-American symbol. Although the flag's symbolism is initially associated with Hispanic ethnicity, some may say Columbus is relevant to the history of the whole continent, and that the sun can be represent the concept of "New World" (as America where known before this name was given) and the liberation process of the continent.
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