AFONSO V, D. (Rei de Portugal).- Carta régia.- Século XV (1473).- 1 f.; 235 x 300 mm. Manuscript on parchment. Royal charter by which King D. Afonso V grants Doctor João Fernandes da Silveira (ca. 1420-1484) the title of Baron of Alvito. Document of great historical importance, concerning the creation of the first barony in Portugal, pushing back by two years the dating presented by historiography. Document given in Torres Vedras, on the 18th day of November 1473. Autograph signature: ElRey. Parchment accompanied by an authentic copy, dated February 7, 1787, signed and bearing the seal of the notary and registrar Bernardo José de Figueiredo e Silva.