Book of the Knight Zifar

The Book of the Knight Zifar (originally Livro del cavallero Cifar, in modern orthography Libro del caballero Zifar) is the earliest fictional adventure tale in prose in the Spanish language.

The first is a fifteenth-century codex known by the letter "M", and catalogued as MS. 11.309 in the Biblioteca Nacional de España in Madrid.

The latter, compiled in 1464, is generally referred to simply as the "Paris manuscript" and is well-illustrated with colourful miniatures.

The book is an adaptation of the legendary life of Saint Eustace, who before his conversion was a Roman general named Placidus (Plácidas in Spanish).

The knight Zifar is a medieval Placidus-cum-Eustace, and his story shares in part the didactic function of Eustacian hagiography, but in other respects is epic and chivalric.