An alliance is a group of nations (players) working together in a scenario. In most scenarios, the alliances are called the "Axis" and "Allies" but they could be anything. In free for all scenarios, each nation is assigned its own alliance or no alliance at all.

Since_triplea_version_1.3.3.0 it is preferred to use relationships instead of alliances. If relationships are set, then alliances will only matter for the stats panel and any game option type victory conditions.

               <alliance player="Germans" alliance="Axis"/>
               <alliance player="Japanese" alliance="Axis"/>
               <alliance player="Italians" alliance="Axis"/>
               <alliance player="British" alliance="Allies"/>
               <alliance player="Russians" alliance="Allies"/>
               <alliance player="Americans" alliance="Allies"/>
               <alliance player="Chinese" alliance="Allies"/>