Liber sine nomine

The Liber sine nomine (The Book without a Name) 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 (Letters to Friends) and assembled in a separate book. In this fashion, Petrarch reasoned, a reader could throw away this collection, and the other letters to friends could be preserved for posterity.

These letters were sent to his closest friends, which many times were well known figures to the public. So that he would not divulge their identities, he withheld these particular 19 letters and published this book "without a name" on any letter. Among these public figures were Philippe de Cabassoles, bishop of Cavaillon; Cola di Rienzo, a political leader; Francesco Nelli, secretary to the bishop Angelo Acciaioli I; Niccola di Capoccia, a cardinal; Lapo da Castiglionchio of Florence; Rinaldo Cavalchini, the son of the notary Oliviero; Stefano Colonna the Elder, the son of Giovanni Colonna who was one of the most important political figures in Rome; and Ildebrandino Conti, a bishop of Padua. In Letter 19, there was an appendix added addressed to the Holy Roman Emperor Charles IV as a final plea to move the papacy back to Rome.

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