As the Babylon station was conceived as a political and cultural meeting place, one of the show's many themes is the cultural and social interaction between civilizations. There are five dominant civilizations represented on Babylon 5: humans, the Narn, the Centauri, the Minbari and the Vorlons; and several dozen less powerful ones. A number of the less powerful races make up the League of Non-Aligned Worlds, which assembled as a result of the Dilgar War, which occurred 30 years before the start of the series.