There were four occupational forces in Berlin at the end of World War II. Berlin, like Germany, had four sectors, Each was occupied by one the victorious allied forces at that time. Three of the forces were to become NATO allies, one of the forces became the leader of Eastern Bloc allies.
The three NATO forces in Berlin were:
*Berlin Brigade of the United States Army
*Berlin Infantry Brigade of the British Army
*French Forces in Berlin
The Eastern Bloc forces in Berlin at that time were from the Soviet Union and Soviet occupied East Germany.
In my opinion, if a category is warranted for one, then a category for each would be appropriate.