1. FC Union Berlin, commonly known as "Union Berlin", was founded in 1966 and is a professional football club based in Köpenick, Berlin, Germany. The club's predecessor, the Oberliga club SC Union 06 Berlin, was established in Berlin and officially formed as "Union Berlin" in East Germany in 1966. After the reunification of Germany, the club spent a long time lingering in lower leagues, finally achieving a historic breakthrough by being promoted to the Bundesliga for the first time in the 2018-19 season.
After being promoted to the Bundesliga, Union Berlin quickly established itself, successfully qualifying for the UEFA Champions League, making the leap from Bundesliga newcomers to European competitors. Union Berlin is known as the "Iron Union", a spirit rooted in a deep working-class tradition and a unique fan culture. The team's extreme overall discipline, strong defense, and efficient tactics have made it a force to be reckoned with in the Bundesliga.