The Cardassian Union is a fictional interstellar state in the Star Trek universe, known for its militaristic and authoritarian government. It is primarily inhabited by the Cardassians, a humanoid species characterized by their distinctive facial ridges. The Union is often depicted as an oppressive regime that seeks to expand its territory through conquest and colonization. The Cardassian Union plays a significant role in various Star Trek series, particularly in Star Trek: Deep Space Nine. The Union's complex relationships with other species, such as the Bajoran people and the Federation, highlight themes of occupation, resistance, and the moral dilemmas of war.