1) Allies and Axis 2) Temporary alliances 1) Blocs 2) Unions 
coalition, coalitions 1. An alliance, especially a temporary one, of people, factions, parties, or nations. 2. An organization of people (or countries) involved in a pact or treaty; alliance, alignment, alinement. 3. A combination into one body; a union. 4. The state of being combined into one body. 5. The union of diverse things into one body, ...