The flag of Vietnamese Revolutionary Army (Việt Nam Cách mạng quân, 越南革命軍), used in Yen Bay mutiny (1930). It was used since 1929 to 1946. The military flag of Vietnamese Nationalist Party (Việt Nam Quốc dân Đảng, 越南國民黨) would be half-red/half-yellow ; red to symbolize its struggle and yellow to stand for the nation (to imply that the Vietnamese people are struggling for their independence).
Originally from vi.wikipedia; description page is/was of Vietnamese Revolutionary Army.svg here.
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