This is the Chinese Imperial Dragon Flag. This flag was once an official flag of China. The dragon represented the emperor and the was for the people.
Flag of the Chinese Empire under the Qing dynasty (1889-1912), details per the restoration of Beiyang fleet researcher .
The Qing dynasty, officially the Great Qing (/tʃɪŋ/), was the last imperial dynasty of China. It was established in 1636, and ruled China proper from 1644 to 1912. It was preceded by the Ming dynasty and succeeded by the Republic of China. The Qing multi-cultural empire lasted for almost three centuries and formed the territorial base for modern China. It was the fifth largest empire in world history.