The Islamic Golden Age began just over a century after the death of its prophet. The Abbasid Dynasty descended from Muhammad's uncle. Claiming closer blood links, in 750 CE they assumed control of the empire and moved the capital from Damascus to Baghdad. The inclusion of non-Arabs in the Ummah (supra-national community) meant the capital became a centre of science, culture, philosophy and invention pulling on the learning of the many civilisations (in all directions) that preceded. This period is bookended with the sack of Baghdad in 1258 CE by the Mongols of Hulagu Khan. Just one example of the shared learning was the inclusion of zero (not in Roman Numerals) and the Hindu number system from an Arabic scholar studying Indian Mathematics, which was then spread to the West by Pope Sylvester II who studied in Barcelona in his youth (where he learnt Arabic).