Amadis de Gaula is a masterpiece of fantastic literature in Spanish and the most famous of the so-called cavalry books, which were all the rage throughout the sixteenth century in Spain. At the end of the 15th century Garci Rodríguez de Montalvo prepared his definitive version, whose oldest known edition is that of Zaragoza 1508, with the name of the four books of Amadís de Gaula, but it is a much earlier work that already existed in three books from the fourteenth century, according to the works of Chancellor Pero López de Ayala and Pero Ferrús. Montalvo confesses to having amended the first three books and to be the author of the fourth. Everything indicates that the original version of Amadis was Portuguese. It has been attributed to various authors: the Portuguese Chronicle of Gomes Eanes de Azurara, written in 1454, mentions as its author a certain Vasco de Lobeira who was armed knight in the battle of Aljubarrota (1385). Other sources say that the author of Amadís de Gaula was a certain João de Lobeira, and not the Basque troubadour of Lobeira.
(Description has been translated into English, Book edition is in Spanish)