Christianity was integrated into the roman empire in 313 ordinary time. The empire split into two divisions and Byzantium in present day Istanbul, then a Greek city became the administrative centre of the eastern roman empire. Differences of opinion between greeks and romans precipitated the split. In 324 the empire was reunited, Byzantium became the new administrative capital and in 330 was renamed Constantinople after roman empire Constantine.
Muhammad is believed to have been born in 570 in Mecca, modern day Saudi Arabia. His military campaigns eventually transformed tribal communities into a cohesive state, and in later years he sent several armies against the Byzantine empire. The Ottoman empire beginning 1299 was named after Osman I and supplanted the Byzantine empire, eventually spanning three continents. At its height the empire stretched from the middle east to southeast europe, central Asia and north Africa. Osman’s ancestory is not widely known. Some say he was Turkish but this is disputed. It is likely that he was of a sunni middle eastern dynasty.
The Ottomans entered Europe during the mid 14th Century, and the victory in Kosovo in 1389 marked the end of serbian power in the region. Was followed by the battle for the bulgarian tsardom and the defeat of Hungary and Poland. Italy was invaded in 1480. Reportedly, control of major trade routes contributed to a flourishing economic period for the Ottomans during the 15th and 16th Century, and by 1493, Constantinople was taken. The Ottomans dominated Iran, Egypt, Jordan Greece, Palestine and the Portugese empire. Moldova became a tributary state. Baghdad was taken from the persian empire, and in 1535 parts of eastern europe and southern Russia were partitioned between Ottomans and persians. There were wars with Spain and Portugal. The Cape of Good Hope, south Africa, a significant trade post resulted in the portugese- Ottoman naval wars of the 16th Century.
The Ottomans were holders of the caliph title, meaning they were leaders of all muslims worldwide, and they remained strong with few exceptions. One major defeat was the campaigns against Persia resulting in the treaty of Nasu Pasha which ceded many parts of eastern Europe and Russia back to Iran. There were other treaties in Ottomans favour.
The emergence of the Saudi dynasty began in central Arabia in 1727. In 1744 Mohammad ibn Saud joined forces with a religious leader and founder of the wahhabi movement, a strictly traditional and suzeraine brand of Islam. There followed more wars. A treaty ended the 18th Century war with Russia and provided freedom of worship for Christian citizens in Moldova and modern day Romania. By around 1800 there were signs the empire was imploding. Ottomans lagged behind europeans in technology, industry and the literacy rate. Only around 5-10% of the population could read and write.
The Ottoman empire experienced unrest in the years leading up to the first world war including the March 31st incident and two further coups in 1912 and 1913. The empire entered the first world war on behalf of Germany and the central powers and were ultimately defeated. The arab revolt began during the war, in 1916, with uk support. An agreement was reached concerning a unified arab state stretching from Syria to Yemen which the british promised to recognise. The british and french later partitioned the middle east into mandate territories. The partition of the Ottoman empire was finalised under the 1920 treaty of Sèvres as designed in the conference of London, and the last sultan of the empire left Turkey on a british war ship.