Almagest is a 2nd century (AD) astronomical and a mathematical treatise and was written in Greek by Claudius Ptolemy. The title ‘Almagest’ is from the Arabic al-majisṭī. Why Arabic? When the Christian Spanish King Alfonso VI captured Toledo in the 11th century, the city which was under the Islamic rule became an important centre for translation of Arabic scientific works into Latin. It is this Latin copy (Almagestum) that was translated into English. The Greek version surfaced in the 15th century.