I'm currently doing a research on the skirmish between these 2 countries. As far as I know, the most first ever controversial issue that bruised the relationship was the first sino-japan war dating back to some 19th century period. Can anyone help me identify whether there were earlier events that contributed to the current and occasional misunderstandings and disagreements to the ties of the 2 countries? thanks. =DD
China fought with Japan during Tang Dynasty, although it might be an issue between them