Mariana Alcoforado (1640 - 1723)

Sóror Mariana Alcoforado was a Portuguese nun, who lived in the convent of the Poor Clares in Beja, Portugal. She is supposedly the real Portuguese author of the Letters of a Portuguese Nun, a book that attained much success in the French literary circles in the 17th and 18th centuries. Even though the authorship is debated, the existence of Mariana herself isn't questioned.