Islam was founded by the Prophet Muhammad. By his death in AD632, Islam was the religion of all of Arabia. By 732, the Islamic empire stretched from the borders of India, through Persia and the Middle East, along the north coast of Africa, and into Spain.
In the 11th century, the Seljuk Turks advanced further. They defeated the Byzantine army at the Battle of Manzikert (1071) and gradually conquered Asia Minor, which is modern-day Turkey.
In the 14th century, a Turkish chieftain, Osman (1326), founded the Ottoman Turkish empire. In the 1350s, the Turks invaded Europe, won the Battle of Kosovo (1389) and gradually conquered the Balkans up to the borders of Hungary. In 1453, they captured Constantinople, the capital of the Byzantine Empire.
The Islamic Empire 622-750
The Turks believed in a prophecy called Osman's dream, about a tree which grew until it covered the whole world. This gave them confidence that they would win a world-wide empire.
The Ottoman armies had two sections:
The Ottoman Empire had huge resources. It attacked smaller states which had been weakened by the Black Death (1347-1348).
The Ottoman Empire lasted an incredibly long time – until after the First World War.