Manchuria existed from the Middle Ages to present-day China.
The Qing dynasty was founded by the Jurchen Aisin Gioro clan in Manchuria in the late 16th Century. Wikipedia:Qing Dynasty
The Qing dynasty ruled Manchuria and China, but ended in 1912 and succeeded into the Republic of China. Ever since then, Manchuria have had little power or authority over there Eastern China territory. Does this push them to get independence? Have they ever tried it before?