Not until 60 BC, during another succession crisis, did the Hsiung-nu empire break up in civil war. It was this war which forced the Hsiung-nu to negotiate a peace with China. The Hsiung-nu had long refused to accept any peace treaty with China because the Han court had insisted that the ho-ch’in system could not be restored and that the Hsiung-nu must enter the tributary system as part of any new agreement.
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Then, in 54 BC, long after the death of Wu-ti and the abandonment of his aggressive policies, the Hsiung-nu accepted China’s terms. From that time onward no nomadic power on the steppe ever seriously objected to the tributary framework. The reason for this sharp change was the discovery that the tributary system was a sham — demanding mere tokens of submission in exchange for huge benefits. Once the Hsiung-nu understood its operation, they actively supported the tributary system, which allowed them to rebuild their power on the steppe.
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The Hsiung-nu demanded hostages and tribute from neighboring tribes to insure the continuation of an exploitative relationship that directly benefited the Hsiung-nu. It was beyond their imagination that China might only be dealing in the symbols of formal submission that had little real meaning. To the pragmatic Hsiung-nu, the world of symbols was confined largely to burning towns and taking heads as a sign of hostility. That China might be demanding only token submission in exchange for a huge increase in gifts, regular subsidies and trade was, to quote Chia I’s phrase in a very different context, ‘““something beyond comprehension — like hanging upside down.”
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Having accepted the framework of the tributary system, the Hsiung-nu immediately set about exploiting it, often showing great sophistication in manipulating Han values to serve their own ends. It was the Shan-yu who controlled the time and frequency of tributary visits, it was he who requested and received special grants of grain, and it was he who received lavish gifts from the Han court with each embassy, while providing his own envoys with only token gifts.