Taikun

Taikun (大君^?) is an archaic Japanese term of respect derived from Chinese I Ching which once referred to an independent ruler who did not have an imperial lineage. Its literal meaning is "Great Lord/Prince" or "Supreme Commander". In the Edo Period, this word was used as a diplomatic title designating the Shogun of Japan in relations with foreign countries, as an attempt to convey that the shogun was more important than the Japanese Emperor. The official name is "Nihon-koku Taikun" (日本国大君^?, Tycoon of Japan).

The term was first used by the Tokugawa shogunate in an attempt to extricate Japan from the Sino-centric system of relations. As Shogun, he certainly could not call himself the Emperor of Japan (天皇, Tennō^?), but he also could not use the term "king" (国王, kokuō^?). As formal language is extremely important in diplomacy, the connotations of most alternative terms were found to be inappropriate, and so taikun was chosen to best represent the shogun in formal diplomatic communications.

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