When the regions which had been ruled by Zhou were politically unified by the Qin dynasty, the notion of "Tenka" became a clear geographical notion which corresponded to the reality in politics.
秦によって、周の支配していた地域が政治的に一元化されて統合されると、現実の政治世界に対応する明確な地理概念として「天下」概念は顕在化した。