Francesco Nelli was the secretary of bishop Angelo Acciaioli I

Angelo Acciaioli I

Angelo Acciaioli I was an Italian Roman Catholic bishop from Florence.- Biography :Angelo was born in Florence of the noble Acciaioli family, the son of Monte, the grandson of Tommaso Acciaiuoli, also known as Mannino Acciaiuoli....

 and a pastor at the Prior of the Church of the Holy Apostles in Florence. Nelli corresponded much with Francesco Petrarch as is evident by the fifty letters still existing of his to Petrarch, and the thirty-eight letters still existing from Petrarch to him. Six of the nineteen letters of Petrarch's Liber sine nomine

Liber sine nomine

The is a collection of nineteen personal letters written in Latin by the fourteenth century Italian poet and Renaissance humanist Petrarch. The letters being harshly critical of the Avignon papacy, they were withheld from the larger collection of his Epistolae familiares and assembled in a...

are addressed to Nelli.