when did it gain its independence?
15 July 1821
Peruvian War of Independence
 The signing of the Act of Independence of Peru was held on 15 July 1821. 
what is pisco sour? An alcoholic cocktail of Peruvian origin where does this country get its name from? It may be derived from "Birú", the name of a local ruler
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Peruvian War of Independence [SEP] Declaration of Independence of Peru
Once inside Lima, General San Martín invited all of the populace of Lima to swear oath to the Independence cause. The signing of the Act of Independence of Peru was held on 15 July 1821. Manuel Pérez de Tudela, later Minister of International Relations wrote the Act of Independence. Admiral Cochrane is welcomed in Lima two days later; General José de San Martín announces in the Plaza Mayor of Lima the famous declaration of independence: