The Seljuk and Ottoman Turkish states

The Ottoman beylik arose in the north-west of Asia Minor, and bordering a weakening Byzantium helped it grow. At the end of the life of the dynasty’s founder Osman (1299–1326) the city of Bursa was taken; his son Orhan took Nicaea and Nicomedia and reached the Black Sea coast, set up the office of vizier, struck coins and divided the army into infantry and cavalry units. In the Balkans there were large states such as Byzantium, Serbia, Bulgaria and Bosnia, but disunity kept them from uniting; the first raids came in the mid-14th century and in the next thirty years the Turks seized most of the Balkans. Sultan Bayezid (1389–1402) won the nickname Yildirim, “thunderbolt”, for the speed of his victories. In the summer of 1402, in the battle near Ankara, Amir Temur’s army defeated Bayezid’s; this event prevented the fall of Constantinople at that time and gave Byzantium about 50 more years. In May 1453 Sultan Mehmed II took Constantinople after a siege, the last Byzantine emperor died in the fighting, and the city became the Ottoman capital, later known as Istanbul. Factors of success: a well-organised cavalry (each horseman was given a timar, land, for his service) and the infantry janissaries, loyal to the sultan. The janissaries were raised from boys taken from Christian families and formed the sultan’s personal guard.