Meanwhile intrigue followed intrigue at the court of Chou; the mutual assassinations within the ruling group were as incessant as in the last years of the great Toba empire, until the real power passed from the emperor and his Toba entourage to a Chinese family, the Yang. Yang Chien’s daughter was the wife of a Chou emperor; his son was married to a girl of the Hun family Tu-ku; her sister was the wife of the father of the Chou emperor. Amid this tangled relationship in the imperial house it is not surprising that Yang Chien should attain great power. The Tu-ku were a very old family of the Hun nobility; originally the name belonged to the Hun house from which the shan-yue had to be descended. This family still observed the traditions of the Hun rulers, and relationship with it was regarded as an honour even by the Chinese. Through their centuries of association with aristocratically organized foreign peoples, some of the notions of nobility had taken root among the Chinese gentry; to be related with old ruling houses was a welcome means of evidencing or securing a position of special distinction among the gentry. Yang Chien gained useful prestige from his family connections. After the leading Chinese cliques had regained predominance in the Chou empire, much as had happened before in the Toba empire, Yang Chien’s position was strong enough to enable him to massacre the members of the imperial family and then, in 581, to declare himself emperor. Thus began the Sui dynasty, the first dynasty that was once more to rule all China.
But what had happened to the Toba? With the ending of the Chou empire they disappeared for all time, just as the Juan-juan had done a little earlier. So far as the tribes did not entirely disintegrate, the people of the tribes seem during the last years of Toba and Chou to have joined Turkish and other tribes. In any case, nothing more is heard of them as a people, and they themselves lived on under the name of the tribe that led the new tribal league.
Most of the Toba nobility, on the other hand, became Chinese. This process can be closely followed in the Chinese annals. The tribes that had disintegrated in the time of the Toba empire broke up into families of which some adopted the name of the tribe as their family name, while others chose Chinese family names. During the centuries that followed, in some cases indeed down to modern times, these families continue to appear, often playing an important part in Chinese history.