The Medici Codex of 1518 is a music book prepared for the Pope Leo X, the second son of Lorenzo the Magnificent of the Medici family, who was pope from 1513 to 1521.
The codex contains 53 motets and was presented to Leo's nephew Lorenzo di Piero de' Medici, Duke of Urbino at his wedding to the French princess Madeleine de La Tour d'Auvergne in 1518.
Edward Lowinsky, in the facsimile edition (1968) proposed that Jean Mouton was the editor. The book contains a tribute motet to Leo Gaude felix Florentia by Andreas de Silva, motets by composers of the Franco-Flemish school, including Jean Mouton, Johannes de la Fage, Josquin Desprez, Pierrequin de Thérache, Adrian Willaert and Inviolata integra et casta es by the Italian Costanzo Festa.