The solemn promise of joining the Workers 'Peasants' Red Army (D. Moore) Soviet Posters (1917-1941)

The picture has something of this: retro, vintage, flag, people, antique, woman, man, symbol, design, bill, card, paper, image, culture.
Perhaps it’s a large poster of a man holding a flag in front of a crowd of men in red and black uniforms, with a red sky in the background.