Italian football,

Milan is one of the best supported football clubs in Italy, according to research conducted by Italian newspaper La Repubblica.[31] Historically, Milan was supported by the city's working-class and trade unionists.[32] On the other hand, crosstown rivals Internazionale were mainly supported by the more prosperous and typically Milanese middle-class.[32] One of the oldest ultras groups in all of Italian football, Fossa dei Leoni, originated in Milan.[33] Currently, the main ultras group within the support base is Brigate Rossonere.[33] Politically, Milan ultras have never had any particular preference,[33] but the media traditionally associated them with the left-wing,[34] until recently, when Berlusconi's presidency somewhat altered that view.[35]
According to a study from 2010, Milan is the most supported Italian team in Europe and seventh overall, with over 18.4 million fans.[11] AC Milan has the ninth highest average attendance of European football clubs behind Borussia Dortmund, FC Barcelona, Manchester United, Real Madrid, Bayern Munich, Schalke, Arsenal, and Hamburg.[36][37][38][39][40]
Genoa fans consider Milan a hated rival after Genoa fan, Vincenzo Spagnolo was stabbed to death by a Milan supporter in January 1995.[41] However, Milan's main rivalry is with neighbor club, Internazionale; both clubs meet in the widely anticipated Derby della Madonnina twice every Serie A season. The name of the derby refers to the Blessed Virgin Mary, whose statue atop the Milan Cathedral is one of the city's main attractions. The match usually creates a lively atmosphere, with numerous (often humorous or offensive) banners unfolded before the start of the game. Flares are commonly present and contribute to the spectacle but they have occasionally led to problems, including the abandonment of the second leg of the 2004–05 Champions League quarterfinal match between Milan and Inter on 12 April 2005, after a flare thrown from the crowd by an Inter supporter struck Milan keeper Dida on the shoulder