American Uniforms
This is a picture of what an American soldier serving in France would've worn. It would include an issue shirt, breeches, puttees, and overseas cap or helmet, dogtags, and an overcoat. They wore puttees (leg wraps) instead of canvas leggings to keep their legs a little bit drier.
Italy Uniforms
Italy's uniforms resembled Imperialism. When the knee-high boots were worn, the pants would be gathered up to the knee. The tunic underneath and their pants are more of a close fit.