This was the first printed edition of Almagest, the book that had dominated medieval and Renaissance astronomy. The Latin translation used for the text had been made from Arabic by Gerard of Cremona in the 12th century. The book was produced by Peter Liechtenstein, a German printer who established a press in Venice towards the end of the 15th century. He was from Cologne, an early centre for printing (where the first printer in England, William Caxton, learned the trade) and had printed other works of astronomy and astrology. Simplified accounts of Ptolemaic planetary theory had been published but the development of mathematical astronomy would depend on a mastery of all its complexities.