southern routes,[31] and we have seen that these conquests accomplished no discernible permanent elevation of prices in the West.[32] In the war of Bayezid II with the sultan of Egypt, during the years 1485 to 1491, caused by the latter’s giving asylum to the former’s brother, Prince Jem, the Turkish troops were thoroughly defeated. The course of oriental trade through Syria and Egypt was not in the least molested by the Turks before the year 1516. Along the northern routes, whose outlets were in their hands, they made no effort to stop the flow of wares. In times of peace and order in Persia many caravans passed east and west, exchanging wares from the Aegean Sea even to the far interior of Asia. There continued also a regular movement north and south to Aleppo, and thence to Bagdad and Mecca and the East. If the Turks had hindered oriental trade, they had checked it but slightly. During their frequent wars commerce was more or less disturbed; but the wars usually ended in an increase of territory which furnished a wider commercial opportunity. Through Egypt and Syria, although disputes about the succession to the Mameluke throne, occasional visitations of the plague, and quarrels between natives and Europeans caused the volume of trade to fluctuate, the old flow of oriental wares was maintained unbroken down to 1502.[33] That year marks a new epoch. The galleys of Venice found very few spices at Alexandria and Beirut; in 1504 they found none at all.[34] The southern trade-routes of the Levant had been emptied by the purchases of the Portuguese in India. From that year an average of twelve or more ships left Lisbon annually for the East,[35] and from 1507 the Portuguese sent fleets to blockade the mouths of the Red Sea and the Persian Gulf.[36] It was a deliberate attempt to stop permanently the passage of wares along the old southern routes of oriental trade, made not by Turks but by western Europeans, but it was not entirely successful. The Venetian galleys which continued to sail to the Levant usually found some spices to be bought. But the old certainty was gone, and prices which were low at Lisbon were high at Beirut and Alexandria.[37] The total quantity of spices which came by the old routes from the East to Europe was greatly reduced. Venice sent fewer ships to the Levant and deemed it imprudent to build new galleys for the Eastern trade.[38] This was the situation when Selim I overthrew the Mameluke sultans in 1516 and 1517. Instead of blocking the southern routes further, he adopted the policy which the Mamelukes had left him. He renewed the old treaties with Venice and the West, and took over the intention of crushing the Portuguese naval power in the Indian Ocean by a fleet sent down the Red Sea.[39]