Iyemitsu suggested that all the daimios should make Yedo their place of residence for half the year. At first they were treated as guests, the shogun meeting them in the suburbs and dealing with them with great consideration. But as the years went on the daimios became more and more like prisoners on parole. They were obliged to pay tribute of respect to the shogun in a manner equivalent to doing homage. Though they could return at intervals to their estates, their wives and children were kept in Yedo as hostages for their good behavior. When Iyemitsu died, the shoguns had cemented their power beyond dispute. The mikados, nominal emperors, were at their beck and call; the daimios were virtual prisoners of state; the whole military power and revenues of the empire were under their control; conspiracy and attempted rebellion could be crushed by a wave of their hands; peace ruled in Japan. Iyemitsu was the first to whom the title of Tai Kun (Tycoon), or Great King, was ever applied. It was in a letter written to Corea, intended to influence foreigners. It was employed in a larger sense for the same purpose at a later date, as we shall hereafter see. Suffice it here to say that the Tokugawas remained the rulers of Japan until 1868, when a new move in the game of empire was made. _THE PROGRESS OF CHRISTIANITY IN JAPAN._ The fact that such a realm as that of Japan existed remained unknown in Europe until about six centuries ago, when Marco Polo, in his famous record of travel and adventure, first spoke of it. He knew of it, however, only by Chinese hearsay, and the story he told contained far more of fable than of fact. The Chinese at that time seem to have had little knowledge of their nearest civilized neighbor. [Illustration: Reproduced by permission of The Philadelphia Museums. RETURNING FROM MARKET. JAPAN.] "Zipangu"--the name he gives it--is, he says, "an island in the Eastern Ocean, about fifteen hundred miles [Chinese miles] from the mainland. Its people are well made, of fair complexion, and civilized in manner, but idolaters in religion." He continues, "They have gold in the greatest abundance, its sources being inexhaustible. To this circumstance we are to attribute the extraordinary richness of the sovereign's palace according to what we are told by those who have access to the place. The entire roof is covered with a plating of gold, in the same manner as we cover houses, or more properly churches, with lead. The ceilings of the halls are of the same precious metal; many of the apartments have small tables of pure gold, of considerable thickness; and the windows have also golden ornaments. So vast, indeed, are the riches of the palace that it is impossible to convey an idea of them. In this island there are pearls also, in large quantities, of a pink color, round in shape and of great size, equal in value to, or even exceeding, that of the white pearls. There are also found there a number of precious stones."