The Period of Expansion The group of Turks that became known as
Ottomans, after their tribal chief Osman, settled in northwest
Asia Minor, near the boundary of the Byzantine Empire, in the
13th century. (For the earlier history of the region, Soon the
Ottomans began pushing the Byzantines back toward Europe. They
were joined by many ghazis (Muslim warriors especially dedicated
to fighting infidels, or nonbelievers) from other Turkish
groups. The Ottomans extended their rule to the Sea of Marmara
by defeating the Byzantines at Nicaea (Iznik) in 1301.Ottoman
Empire: The Beginnings The Ottoman Empire started as a small
state around Bursa in Anatolia (now Turkey). By the end of the
15th century, the empire had expanded into eastern Europe.
During the 15th century, elite military units made up of
soldiers called Janissaries were created. The Ottomans crossed
into Europe and continued their conquests. Efforts by the
Serbians and Bulgars to stop the Turks failed, Tamerlane, a
Tatar chieftain, led an invasion of Asia