This work is a Latin translation of al-Farghānī’s influential and well-known Kitāb jawāmiʿ ʿilm al-nujūm wa uṣūl al-ḥarakāt al-samāwīya (Book of generalities of astronomy and bases of celestial motions). Aḥmad ibn Moḥammad ibn Kathīr al-Farghānī was an astronomer who flourished at the court of the early Abbasid caliphs. He appears to have been active in the court of al-Ma’mun. If he is the same figure who is said to have been entrusted by al-Mutawakkil with the construction of the nilometer in Cairo, then he would have been active from the early decades of the ninth century to his death in 861 (spanning the rules of al-Ma’mun, al-Muʿtaṣim, al-Wāthiq, and al-Mutawakkil). Al-Farghānī, the name by which the astronomer would have been known at the Abbasid court, and which was Latinized to Alfraganus, indicates the Ferghana Valley (in present-day Uzbekistan) as his birthplace, in the Persian or Perso-Turkic cultural realm of Central Asia. The same work by al-Farghānī has various titles in Arabic, including Kitāb fī uṣūl ‘ilm al-nujūm (Book of generalities of astronomy and bases of celestial motions) and Kitābal-hay’afī fuṣūlal-thalāthīn (Book on the configuration [of the heavenly spheres] in thirty chapters). The work originally was translated into Latin by Johannes Hispalensis (John of Seville, flourished mid-12th century), and Gherardo da Cremona (circa 1114–87). It was also translated into Hebrew by Jacob Anatoli (1194–1256). The Latin edition presented here is the translation by Jacob Christmann (1554–1613) of Anatoli’s Hebrew translation, published in Frankfurt in 1590. Christmann includes a lengthy commentary on the Egyptian, Roman, and Persian calendars, which was likely derived from Anatoli. Christmann also adds an appendix to al-Farghānī’s work, at the conclusion of which he mentions his difficulties in editing al-Farghānī while lacking suitable Arabic copies of the work, bemoaning as well the obscurities remaining in his translation. Invoking the help needed from printers in Italy and Spain, he envisions a time when an authoritative copy of al-Farghānī’s work will become available. This lament by a Renaissance humanist in 1590 about the difficulty of printing a scientific work that predated his era by more than seven centuries is a telling detail that highlights the influence that scientific texts produced in the Islamic lands had on Renaissance Europe. Christmann dedicates his translation to the German prince, Johann Casimir, Count Palatine of the Rhine (1543–92).