Joaquim Machado de Castro (19 June 1731 – 17 November 1822) was one of Portugal's foremost sculptors. He wrote extensively on his works and the theory behind them, including a full-length discussion of the statue of D. José I entitled Descripção analytica da execucão da estatua equestre, Lisbon 1810.
Machado de Castro was born in Coimbra, and was a celebrated figure throughout Europe in the eighteenth and early nineteenth centuries. The Descripção is the artist's detailed comments on the style and execution of his finest work, the equestrian statue of D. José I, erected in 1775 as part of the rebuilding of central Lisbon after the disastrous earthquake of 1755. The stages of construction are illustrated with sections and cross-sections of the horse and rider, views of the statue from different angles, and details of armor and ornamentation. This bronze statue remains one of Lisbon's most important monuments, and dominates one of the major squares of Europe, the Praça do Comércio or Terreiro do Paço. In the introduction, Machado de Castro comments on similar works of art in the rest of Europe.