Career
Bonatti was advisor of Frederick II, Holy Roman Emperor, Ezzelino da Romano III, Guido Novello da Polenta and Guido I da Montefeltro. He also served the communal governments of Florence, Siena and Forlì. His employers were all Ghibellines (supporters of the Holy Roman Emperor), who were in conflict with the Guelphs (supporters of the Pope), and all were excommunicated at some time or another.
Bonatti"s astrological reputation was also criticised in Dante"s Divine Comedy, where he is depicted as residing in hell as punishment for his astrology.
His most famous work was his Liber Astronomiae or "Book of Astronomy", written around 1277. This remained a classic astrology textbook for two centuries.
Bonatti"s dates of birth and death are unknown, the latter probably occurring between 1296 and 1300. This has been contested as Bonatti, expressed great disdain for Franciscans in his early period.
The celebrated physicist, astronomer and astrologer, Guido Bonatti (d 1296), a Friar Minor, drew scholars to his professional chair from all parts of Europe.
He wrote Theoria Planetarum (printed at Venice, 1506) and Liber Astronomicus. According to the uncorroborated account of the Italian historian Ludovico Antonio Muratori, Bonatti was murdered by robbers whilst returning from a study trip to Paris and other Italian cities, being set upon in or near Casena, with his body left upon the road. Evidence from various accounts establishes that Bonatti was in his eighties when he died.
