It has been shown that hitherto in the Ottoman conquests in Asia Minor at the expense of the Byzantine Empire a great proportion of the Christian population embraced Islam; and it may well have been that the spread of Islam and the conversion of infidels to the true faith were in part the incentives for the expansion of the Ottoman Empire. But henceforth, after the organization of the army by Orchan and Murad and the great rewards held out to the soldiers for the conquest of non-Moslem territories, it does not appear that the Ottoman armies were inspired by any missionary zeal for the spread of Islam. The main, if not the sole motives, were loot and plunder, the sale of captives as slaves, and the confiscation of land and its distribution among the soldiers as fiefs; and these objects were attained to a far greater extent by the invasion of Christian States in Europe than by the extension of the Empire over Moslem countries in Asia. In the year 1354 Orchan, after completing the organization of his army, turned his attention for the first time to Europe. Thenceforth, till his death in 1359, his restless ambition was directed against the Byzantine Empire. Advancing age prevented his taking the field himself at the head of his army. But his eldest son, Solyman, who had all the great qualities of his race, and who was the idol of the army, took his place in command of the invading forces. It may be well to point out here that, at this time, the middle of the fourteenth century, the Byzantine Empire was already reduced to very insignificant proportions, compared to its ancient grandeur. The territories subject to it, which for centuries had extended to the Danube in Europe, and in Asia over Anatolia and Syria, had been already greatly diminished when the leaders of the fourth Crusade, in 1204, in one of the most disgraceful episodes in history, turned aside from their avowed object of attacking the Moslems in Palestine and, in lieu thereof, attacked and captured Constantinople, and compelled the Byzantine Emperor to transfer the seat of his government to Nicæa, in Asia Minor. There followed the brief period of the Latin Empire. But in 1261 the Byzantine Greeks reconquered Constantinople, and the ephemeral Latin Empire disappeared from history. The Byzantines were then able to recover a small part only of their old dominions in Europe and Asia. At the time when Orchan, who had driven them from Asia, decided to attack them in Europe, they held there no more than Thrace with Adrianople, a part of Macedonia with Salonika, and the greater part of the Morea in Greece. To the north of them Serbia, under Stephen Dushan, the most eminent of its rulers, had asserted supremacy over the greater half of the Balkan peninsula, was threatening Salonika, and had ambition to possess himself of Constantinople. Bulgaria, though it had lost territory to Serbia, still possessed the smaller half of the Balkans.