| Since the Eastern Zhou Dynasty, the status and power of Zhou royal court had declined and the feudal kingdoms constantly sent the punitive expedition to annex each other. However, thanks to exchanging hostages, the destructive effect of the expedition was reduced to some extent. During the Spring and Autumn period, the number of sending hostages was about 20. In these sendings, there were an obvious contrast in the strength of both sides and in most cases the small countries sent hostages to the powerful ones unilaterally, which were mostly overlords in Central Plains at that time. During the Warring States period, the feudal kingdoms exchanged hostages reciprocally in order to request reinforcement or ease diplomatic relations. The different characteristics of exchanging hostages during the two periods reflected the evolution of the feudal kingdoms'strength. At the same time, the feudal kingdoms pursued the power which was no worse than the Zhou Dynasty by sending the punitive expedition and entering into an alliance. In this process, the feudal kingdoms established and validated their subordination by exchanging hostages, which was an important political moral in the hostage during the Spring and Autumn and the Warring States period. |