The unlikely roots of the Ottomans are revealed by Rageh Omaar. From nomadic horsemen, in a rural backwater of modern day Turkey, they became rulers of a vast empire spanning three continents. At an incredible speed they came to rule over Baghdad and Cairo in the south, where they controlled the holiest sites of Islam - Mecca, Medina and Jerusalem, and they reached deep into Europe, taking in Sarajevo and threatening the gates of Vienna.