Edwin Pears 
The Ottoman Turks to the Fall of Constantinople [EPUB ebook] 

IT was in 1299 that Osman (Othmain, Uthman) declared himself Emir of the Turks, that is, of the tribe over which he ruled. The Seljuq Turks have been treated in a previous chapter; but there were many other Turkish tribes present in the middle and at the end of the thirteenth century in Asia Minor and Syria, and, in order to understand the conditions under which the Ottoman Turks advanced and became a nation, a short notice of the condition of Anatolia at that time is necessary. The country appeared indeed to be everywhere overrun with Turks. A constant stream of Turkish immigrants had commenced to flow from the south-west of Central Asia during the eleventh century, and continued during the twelfth and indeed long after the capture of Constantinople. Some of these went westward to the north of the Black Sea, while those with whom we are concerned entered Asia Minor through the lands between the Persian Gulf and the Black Sea.