Most of Africa was colonies of one European nation or another during the war. The German Empire had a few African colonies, such as German East Africa. But Germany's opponents had a lot more, France, Great Britain, Italy and Belgium. Portugal had a few colonies in Africa too. French Colonial troops, such as the Senegalese, fought on the western front, in the trenches.
Germany was on the losing side of World War 1.
The side that lost world war 1 is central powers
japan
Britain's side
The allies
Turkey joined Germany in World War 1
france
on the allied side
Allies (british, French side)
Japan and Italy fought against Germany in World War 1 but were on Germany's side in World War 2
Italy
It was during World War 1 that all races fought side by side for America.