[Soldiers in training, Tai'erzhuang, Xuzhou front, China]

[Soldiers taking a break from training, Tai'erzhuang, Xuzhou front, China]

[Soldiers and peasants with donkeys and bundles of food for soldiers, Tai'erzhuang, Xuzhou front, China]

[Leon Trotsky lecturing, Copenhagen]

[Child next to barricade, near Barcelona, Spain]

[Republican soldiers lying down and crouching on the ground, Santa Eulalia, Aragón front, Spain]

[An officer holds his hat as he gives a talk to militamen, Andalusian front, Spain]

[Republican soldiers firing machine guns, University City, Madrid]