The Dominion War was a major conflict in the fictional universe of Star Trek, primarily depicted in the series Star Trek: Deep Space Nine. It involved a coalition of forces from the United Federation of Planets, the Klingon Empire, and the Romulan Star Empire fighting against the Dominion, a powerful empire from the Gamma Quadrant led by the Founders and their genetically engineered soldiers, the Jem'Hadar. The war began in 2373 and lasted until 2375, resulting in significant losses on both sides. Key battles took place in various star systems, and the conflict highlighted themes of alliance, sacrifice, and the moral complexities of war. The war concluded with the defeat of the Dominion, leading to a fragile peace in the Alpha Quadrant.