During the forty-six years of his reign Solyman added enormously to the Empire. Belgrade, Rhodes, nearly the whole of Hungary, the Crimea, the great provinces of Mossul, Bagdad, and Bassorah, and a part of Armenia taken from Persia, Yemen and Aden in Arabia, Algiers, Oran, and Tripoli, and an undefined extent of hinterland inhabited by Arabs in North Africa, and a wide extension of Egypt in the direction of Nubia, were the contributions which he transmitted to his successors. There were few years of his long reign in which he was not under arms. War with Hungary and Austria in the north alternated with war with Persia in the east and with Spain in the west. Solyman was often in command of his armies. He conducted personally thirteen campaigns, some of them, such as those against Persia, extending over two years. For the most part these wars were embarked on without any just or even plausible cause. They were stimulated by lust of conquest on the Sultan’s part, and by craving for active service and for loot on the part of the Janissaries. Religious fanaticism seems to have had little concern with the motives or results of them. Solyman’s first campaign, in 1521, was directed against Belgrade, the city which had successfully defied Mahomet II. He marched against it at the head of an army of a hundred thousand men with three hundred guns. It was bravely defended by the Hungarians. But they had no guns. After seven days of bombardment the city was assaulted and captured. There was no massacre of the garrison or the inhabitants. Solyman converted the principal church into a mosque. The city was thenceforth garrisoned by a Turkish force. It constituted the principal stronghold of the Empire on the Danube, and was the gateway for many invasions of Hungary.