This is a Chinese Nationalist flag from the Chinese Civil War (1926-1949). The flag features the Kuomintang (Chinese Nationalist Party) emblem in the upper corner. A white piece of cloth on the side is used to attach to the flag to a small pole. Judging by the size (32 × 21cm) it was likely a personal flag owned by a Chinese Nationalist.

The Republic of China, today located on the island of Taiwan, officially adopted the flag on May 5, 1921. It is the current flag of the ROC.

"The 12 points of the white sun in the emblem represent the Chinese conceptualization of day’s being divided into 12 two-hour periods, which symbolize unceasing progress. At one level, the three colors of the blue, white, and crimson stand for the Three Principles of the People: nationalism, democracy, and social well-being. At another level, the colors embody qualities that evoke other concepts enumerated in the Three Principles: the blue signifies brightness, purity, and freedom, and thus a government that is of the people; the white, honesty, selflessness, and equality, and thus a government that is by the people; and the crimson, sacrifice, bloodshed, and brotherly love, thus a government that is for the people."1

China Chinese Civil War

Description by Samuel Grubb and Jordan Winter