In Celtic mythology, the battle between the Tuatha Dé Danann and the Fomorians represents the struggle between the forces of light and darkness. This conflict symbolizes the transition of Irish culture from paganism to more structured beliefs, showcasing themes of resilience and the quest for rightful governance. The Tuatha Dé Danann emerged victorious, establishing a legacy of powerful deities who influenced aspects of nature and society. This mythology highlights the importance of struggle and balance in cultural identity.