This increase in number of _miyake_ was in itself the increase of the wealth of the imperial family, and the increase of its power at the same time. It is a matter of course that such growth of the imperial family contributed largely to the increase of the imperial power itself, and was therefore a step toward centralisation. With a family as centre, however, a strong centralisation was impossible at a time when there was no definite regulation concerning the succession. The law of primogeniture had not yet been enacted. Princesses were not excluded from the order of succession. In such an age too strong a centralisation with the family as its nucleus, if it had been possible, could only have been a cause of constant internal feuds. The interests of certain members of the imperial family might have come into collision with those of the reigning Emperor, and indeed such clashes were not rare. Besides this weakness which was like a running sore in the process of centralisation, there was another great drawback to the growth of the imperial power. This was the increase in power and influence of certain chieftains. At first there were many chieftains of nearly equal power, and as none among them was influential enough to lord it over all the others, it was not very difficult for the imperial family to avail itself of the rivalry that prevailed among them and to control them accordingly. Some families among the chieftains, however, began to grow rich and powerful like the imperial family itself, while the greater part of them remained more or less stationary, so that a wide gap between the selected few and the rest as regards their influence became perceptible. Thus five conspicuous families, those of Ohtomo, Mononobe, Nakatomi, Abe, and Wani, first emerged from the numerous members of the chieftain class. The family of the Soga, which was descended from Takeshiuchi, the minister of the Empress Jingu, became afterwards very prominent, so that only two of the former five, namely, the Ohtomo and the Mononobe, could cope with it. Among the three which became prominent in place of the former five, the older two continued to be engaged exclusively in warlike business, while the third provided both ministers and generals. The magnitude of their influence in the latter half of the fifth century can be well imagined from the fact that the Emperor Yuryaku complained on his death bed that his vassals' private domains had become too extensive.