The Castiglioni Planisphere is a large nautical map drawn on four parchments which are pieced together for total dimensions of 81.5 × 214 cm (32.09 x 84.25 in). The map, which indicates the known world in 1525, is attributed to Diego Ribeiro, “piloto maior” of the Casa de Contratación in Seville - the office of the Spanish Crown charged with representing new geographic discoveries on maps - and it is considered to be of exceptional interest as it is among the first to visually document the theories on the sphericity of the Earth.
The map was a gift from Emperor Charles V to Baldassare Castiglione, papal nuncio in Spain and author of the acclaimed work, The Book of the Courtier, and it has always been stored at the Castiglioni family archives in Mantua.
In summer 2000, the Italian State bought it and assigned it to the Biblioteca Estense in Modena, which was already home to a significant collection of maps. The Planisphere is now displayed on a panel and exhibited in the Giuseppe Campori room of the library.
The Castiglioni Planisphere has been the subject of an in-depth historical and scientific study (Ernesto Milano), complete with transcription and toponomastics (Annalisa Battini), published in the commentary to the reproduction sponsored by the Ministry of Culture, and curated by Roberto Bini through the coproduction by Il Bulino and the Biblioteca Estense Universitaria. There was a worldwide exclusive limited-edition of 499 numbered and certified copies.