Baltasar Jaime Martínez Compañón (circa 1735–97) was a Spanish-born priest who in 1767 was sent by King Charles III to serve in the Viceroyalty of Peru, initially as choirmaster of Lima Cathedral. He was named bishop of Trujillo in 1778. He remained in Peru until 1791, when he was appointed archbishop of Bogotá. Known for founding towns, building schools, and his efforts to educate the Indians of Trujillo, Martínez Compañón also was responsible for the Codex Trujillo del Perú, a nine-volume compilation of more than 1,400 illustrations and drawings by anonymous authors that he commissioned. These volumes are believed to have been accompanied by a manuscript that has not been found. Each volume deals with a different set of topics. Volume I depicts members of the religious orders present in Peru and other people whose identities are not known, but who undoubtedly represent crown officials. Volume II illustrates the general aspects of Indian life, particularly medical and healing practices, as well as colonial society and its different strata. Volumes III, IV, and V are dedicated to the flora of Peru. Volumes VI, VII, and VIII deal with wildlife, including animals, birds, and cetaceans. Volume IX contains illustrations of archaeological sites related to the Indians of Peru. Presented here is Volume I. It is unclear how this tome entered the collection of the National Library of Colombia; however, the importance of the graphic work in the codex as a record of 18th-century Peru is beyond doubt.