The US 370th Infantry Regiment, the only African American regiment of WWI to be entirely commanded by black officers. They were nicknamed the "Black Devils" by the German for their fierce fighting. It alongside the 369th Infantry Regiment (the "Harlem Hellfighters" popularized by the Battlefield 1 videogame) were assigned to the French Army (hence the French Colonial Adrian helmet slightly mismatched with the US uniform, and French belt pouches), because the white American soldiers didn't wanted to fight alongside black people.
The French, already used to fight alongside non-white soldiers from regiments of the colonies (such as the famous Senegalese Tirailleurs) and with the defense of their country at stake, didn't give a rat-ass of the skincolor, and welcomed them with open arms.