Fudbalski Klub Sarajevo (English: Sarajevo Football Club) is a professional football club based in Sarajevo, the capital city of Bosnia and is one of the most popular clubs in the country. Founded on 24 October 1946, the club was the most successful club from SR Bosnia in former SFR Yugoslavia, winning two Yugoslav First League titles and finishing 5th in that competition's all-time table. Today, FK Sarajevo is one of the most prominent members of the Bosnian Premier League, where it has won two Premier League championship and four Cups.
FK Sarajevo was established on 24 October 1946 as the result of a merger between football teams Udarnik (Vanguard) and Sloboda (Liberty). The club first appeared on the Yugoslav sports scene in 1946 under the name SD Torpedo. It played its first match on 3 November 1946. In 1947, the name was changed to SDM Sarajevo, before changing to the current name in 1949.
FK Sarajevo first entered the top-flight Yugoslav First League after eliminating Belgrade club Sloga. They drew the first match 3–3 in Novi Sad, but then won second match 5-1 in Sarajevo. The team were relegated after their first season in the First League, but were promoted back immediately in 1950. From then, FK Sarajevo played in every season of the First League apart from 1957–58.
A key player for Sarajevo in their early years was the striker Asim Ferhatović, nicknamed Hase, who played for the club from 1952 to 1967. In 1963-64, his total of 19 goals made him the top scorer in the First League, while the club finished fourth, finishing runner-up (to Partizan Belgrade)  for the first time in the following season.
Sarajevo won their first Yugoslav First League title in 1966-67, becoming the first champion from Bosnia. On 24 May that season, the club were denied a double as they lost to Hajduk Split at the Croatian club's ground in the Yugoslav Cup final. The league triumph qualified Sarajevo to the 1967-68 European Cup, where they played their first tie against Cypriots Olympiakos Nicosia, winning 5-3 on aggregate. In the second round, Sarajevo were knocked out 2-1 on aggregate by eventual champions Manchester United of England, despite hosting a goalless draw in the first leg. Sarajevo players during this era included Boško Antić, Mirsad Fazlagić, Vahidin Musemić and Boško Prodanović.
Sarajevo had a second successful spell in the 1970s and 1980s, led by attacking midfielder Safet Sušić who played from 1973 to 1982. In 1978-79, Susic scored 15 goals and was named Player of the Season as Sarajevo finished fourth. The following year, Susic's 17 goals helped retain his Player of the Year title, but he was also joint top scorer in the league. The club came runner-up that season, seven points behind Red Star Belgrade, therefore qualifying for the 1980-81 UEFA Cup. Sarajevo were knocked out there in the first round by German club Hamburger SV, who won 7-5 on aggregate.
Sarajevo returned to the UEFA Cup in 1982-83, beating Bulgaria's Slavia Sofia 6-4 in the first round  and Romanian club FC Corvinul Hunedoara 8-4 in the second, thanks to a 4-0 home win in the second leg. In the third round (last 16), Sarajevo lost their first leg 6-1 to Belgian club RSC Anderlecht, and despite winning the second leg 1-0, were eliminated by the eventual champions. Sarajevo also reached the Yugoslav Cup final that season, losing 3-2 to Dinamo Zagreb in Belgrade.
Sarajevo won their second championship title in 1984-85, finishing four points ahead of runners-up Hajduk Split. The triumph qualified the club for the first round of the 1985-86 European Cup, where they lost both legs to Finnish club Lahti.
The Bosnian War in the early 1990s shut down competitive football in the territory, and as a result FK Sarajevo became a touring club in 1993, featuring players such as Fuad Muzurović, among others played Elvir Baljić, Almir Turković and Mirza Varešanović. Many of the club's supporters, including the infamous Horde Zla (Hordes of Evil) joined the Bosnian army and fought in the war. FK Sarajevo played a friendly game against the local peacekeepers in 1994, and won 4–1.
In 1994-95, the first-ever Bosnian championship was held. Sarajevo came first in their six-team league in Jablanica, and came runners-up in the final league in Zenica, behind local club NK Čelik. Sarajevo again finished as runners-up to Celik in 1996-97 (by two points), but beat the Zenica-based club in the Cup final and Super Cup. The Cup was retained the following year, and despite finishing third in the league, Sarajevo was runner-up due to play-offs. In 1998-99, Sarajevo came first in the league before winning the play-off final against NK Bosna, but lost 1-0 to the same club in the Cup final.
Sarajevo were runners-up in the Bosnian Premier League in 2006-07, but won their second title the following season, beating Zrinjski Mostar by three points.
Sarajevo have been a regular in Europa League qualification in the 21st century, but are yet to make the group stages. Off the back of their 2006-07 league title, Sarajevo played in the UEFA Champions League for the first time in its current format. They beat Maltese champions Marsaxlokk 6-0 away in their first game, eventually winning 9-1 on aggregate. The second round saw Sarajevo defeat Belgians KRC Genk on away goals due to a 2-1 away win in the first leg, although the club were knocked out in the play-off for the Group Stage by Ukrainian team Dynamo Kiev who won 4-0 on aggregate.
In 2004, Safet Sušić, who played at FK Sarajevo from 1973 to 1982, was voted Bosnia's best player of the last 50 years at UEFA's Golden Jubilee. 
FK Sarajevo's rivalry with fellow Sarajevo club FK Željezničar is mainly focussed on the former animosity between the capital's working class and elite, although in recent years residents of all classes have supported both teams. During the post-conflict FK Sarajevo has close ties to current political elite in Bosnia and Herzegovina as it did with local municipal leaders prior to the war and FK Željezničar is rooted in the working class, this derby came to represent the "conservative centripetal forces".
As of 15 May 2009, 95 Sarajevo Derbies have been played in league competition, with 29 wins by either club and 37 draws. Of the 32 matches played in the Bosnian Premier League. FK Sarajevo have won 10 times, compared to 8 by Željezničar.
FK Sarajevo play at the Asim Ferhatović Hase Stadium, formerly known as the Koševo Stadium.
The stadium was opened in 1947. In 1984, it was reconstructed for the 1984 Winter Olympics, and is therefore often called the Olympic Stadium. Officially, however, it is still called "Asim Ferhatović Hase Stadium".
The ground has held matches for Sarajevo and their local rival FK Željezničar, including European matches against clubs such as Manchester United FC and Hamburger SV.
The stadium's largest attendance was recorded in a 1981-82 league match between FK Sarajevo : FK Željezničar. Allegedly, about 60,000 people attended the game.
The club's supporters were historically called Pitari while an individual was, and is still, known as a pitar. Their rowdiness during the matches of the time provoked accusations of being dangerous. During a big season game in 1986 a maroon painted snake was thrown off the east stand onto the visitors bench. This is considered the reason club officials opened the North stand of the AFH (Asim Ferhatović Hase) Stadium to the most enthusiastic of fans. Soon after, the name The Horde Zla was born, when several members of the Pitars created a new identity based on a Zagor comic book of the same name. Today, Pitari and Horde Zla are interchangeable. The Horde Zla became the fastest growing youth organisation in the city of Sarajevo, financing itself through a very well organised, vertically integrated marketing system, as well as a very rigid members policy. During the late 1980s and early 1990s The Horde Zla became infamous for a few of the largest interfan riots and stadium troubles in former Yugoslavia, including the 1991 stabbing of two FK Partizan supporters in front of the FK Partizan stadium in Belgrade and the 1988 riots in the city of Mostar before a league game, resulting in the stabbing of a Mostar resident and the destruction of huge amounts of property. Unlike most other ultra firms in the former Yugoslavia, The Horde Zla considered themselves as Bosniaks and the other firm's national orientation was often a cause for the troubles created by The Horde Zla, as was in a 1989 basketball game when KK Bosna played KK Crvena Zvezda. When the Bosnian war began, most members of The Horde Zla joined the newly formed Army of the Republic of Bosnia and Herzegovina in an effort to defend their city and newly independent state, and many did not survive. Today a plaque exists, to honor The Horde Zla who died defending their city and country. After the war The Horde Zla again took their place on the North stand of the AFH (Asim Ferhatović Hase) stadium on the 10th anniversary of the firm's founding. The Horde Zla again were on the front pages when, during the 1998 Sarajevo derby against Željezničar, they invaded the pitch after some members of the Željezničars firm, The Maniacs attacked the FK Sarajevo goalkeeper, resulting in a huge on-pitch-fight resulting in over 30 serious injuries and setting on fire the stadium's rubber athletics track. The Horde Zla again made headlines in October 2009, during the infamous Široki Brijeg football riots. The riots resulted in the death of Vedran Puljić, a member of Horde zla and over thirty serious injuries, including four gunshot wounds. In July 2012, they clashed with Levski Sofia supporters in the first leg of a UEFA Europa League match that was held in Sofia, Bulgaria.