Connoisseurs of historical details say that during the Spanish era, the rulers required that the baro of the indio be made of flimsy material so that he could not conceal weapons on his person.
Supposedly, the indio was also prohibited from tucking in his shirt, to designate his low rank and to tell him apart from the mestizaje and insulares.
In a lighter vein, some speculate that the indio’s baro did not have pockets because he was poor and did not have money to put in them anyway.
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Source:
Barong Tagalog. http://www.filipinoheritage.com/costumes/barong_tagalog.htm
