This letter was found in the collection Coleção de Cartas (within Cartas Missivas and Other Documents) which collects, in 4 packs, loose documents of uncertain or incomplete date. The contextualization of each letter is done using information from the letter itself. The author and the addressee of the letter were two of the five children (from his first marriage) of António Carneiro, principal secretary of Dom Manuel I. Dona Margarida de Alcáçova was married to Rui Mendes de Vasconcelos (6th lord of Figueiró) , with whom she had two children.
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