Question: What Italian professional football club, founded in 1899, was the first to establish an ultras group?

Context paragraphs:
List of A.C. Milan records and statistics: Associazione Calcio Milan are an Italian professional football club based in Milan, Lombardy.  The club was founded as Milan Foot-Ball and Cricket Club in 1899 and has competed in the Italian football league since the following year.  Milan currently play in Serie A, the top tier of Italian football.  They have been out of the top tier in only two seasons since the establishment of the Serie A as the single division top tier.  They have also been involved in European football ever since they became the first Italian club to enter the European Cup in 1955.

Ultras Junoon: Ultras Junoon is the first ultras group in the UAE that supports the Dubai-based UAE Pro-League football club Al Wasl FC.  The Ultras was founded in 2010 by a group of Al Wasl fans.  Ultras Junoon raised a tifo for the first time at a match against Al-Wahda S.C.C. on August 27, 2010.  The tifo had sheikh Ahmed bin Rashid Al Maktoum's picture on it, he is the owner of Al Wasl FC.  Ultras Junoon also supports the Al-Wasl futsal, basketball, and handball teams.

The Maniacs: The Maniacs (Bosnian: "Manijaci" ) are Ultras group of Bosnian football club FK Željezničar Sarajevo.  There is also subgroups like Blue Tigers, Joint Union, Urban Corps, Stari Grad and Vendetta.

Ultras White Knights (UWK): Ultras White Knights often referred as UWK is an Egyptian Ultras group that supports Zamalek SC in every sport.  It was founded on 17 March 2007 and became the first ultras in the Mena region.

Bad Blue Boys: Bad Blue Boys are an ultras group who support the Croatian football club GNK Dinamo Zagreb and Futsal Dinamo.

Fossa dei Leoni: The Fossa dei Leoni, also referred to by the acronym FdL, was an association of ultras supporters of Italian professional football club Associazione Calcio Milan.  Established in 1968, it was the first ultras group to form in Italy.

Horde Zla: Horde zla (English: Hordes of Evil or Gang Evil) is the organized Ultras group that supports Bosnian football club FK Sarajevo.  The group's logo consists of a stylized depiction of the Grim Reaper, borrowed from a Zagor comic book at the time of the group's inception.  Horde zla is one of two major football fan groups in Bosnia and Herzegovina.  Apart from FK Sarajevo, the group also supports KK Bosna Royal and RK Bosna Sarajevo.  The group's organizational structure is fairly decentralized with many subgroups present at the stadium's north stand - the gathering point of the club's most loyal and passionate fans.  Some of the most well known subgroups are Outlaws, DC, Vutrasi, Fina Gradska Raja and Downtown.  Since FK Sarajevo enjoys a lot of support outside of the capital as well, various subgroups exist in cities across the country.  The group as a whole traditionally maintains very close relations with Dynamo Dresden Ultras.

A.C. Milan: Associazione Calcio Milan (] ), commonly referred to as A.C. Milan or simply Milan, is a professional football club in Milan, Italy, founded in 1899.  The club has spent its entire history, with the exception of the 1980–81 and 1982–83 seasons, in the top flight of Italian football, known as Serie A since 1929–30.

Ultras Ahlawy: Ultras Ahlawy (UA-07) is an Egyptian ultras group that supports the Cairo-based Egyptian Premier League football club Al Ahly SC.  The group was founded in 2007 by former members of the first Ahly support group, Ahly Fans Club (AFC).  Ultras Ahlawy raised its banner for the first time at a match against ENPPI on 13 April 2007.  Ultras Ahlawy also supports the Al Ahly basketball, volleyball, and handball teams.

Tigers Ultras: Tigers Ultras or Tigers Club is the name of the ultras group of Greek football team Asteras Tripolis F.C.  and basketball team S.E.F.A. Arkadikos BC, based in Tripoli, Greece.  Found in 2006, it is the first fan base dedicated to any Arcadian team.  Their logo is the face of a tiger in front of a yellow star (which is Asteras’ logo).

Supporting paragraphs: Fossa dei Leoni A.C. Milan
Answer: A.C. Milan