- Aug 2013
- United States
Others were forced to care because of trade laws. The Chinese recognition of Joseon as prestieged member of the tributary system meant that Out of Northeast Asia, only Korea could trade with China. Japan and Manchuria could not trade with China because they were not deemed civilized enough. This is why British and Dutch played along with being tributary atates to China because only tributaries can legallly trade with china. Thus, if Korea could trade with china, Korea could trade with Japan/Manchuria, and Japan/Manchuria could not trade with china, Korea reaped great profit by playing the middleman between the China/Manchuria/Japan trade and taking a cut from all the transactions. Japan was very furious wih this arrangement because it left them impoverished. The Imjin war is sometimes analyzed to have the second objective of securing profitable trade routes with the biggest market in the world at the time(even today), China.
The idea was that the civilized state (the hegemonic power) would cultivate hierarchic relations with friendly barbarian states to create buffers between them and the hostile barbarians. The friendly peripheral state agreed to remain loyal to the hegemonic power in exchange for political legitimization and trade benefits. As long as the "vassal" did not work against the central state, they didn't really care what they did internally or even internationally, generally speaking (at least in the case of Korea). From a rhetorical perspective, this also boosted the emperor's prestige based how large his sphere of influence was, since his job as heaven's representative was to rule and civilize the earth. The hegemonic power also would rank its different "vassal states" based on various criteria which of course had implications for international diplomacy and rhetoric.
The tribute-investiture system was mutually beneficial, hence why most peripheral "vassal" states took the first step in establishing such relations.
So as far as I can tell the "vassals" were typically independent and fully sovereign in all but the strictly Westphalian sense (i.e. that the state is not part of an international system that has some formal influence their decisions in one way or another).