The club was founded in 1884 as Leicester Fosse F.C., playing on a field near Fosse Road. They moved to Filbert Street in 1891, were elected to the Football League in 1894 and adopted the name Leicester City in 1919. They moved to the nearby Walkers Stadium in 2002, which was renamed the King Power Stadium after a change of ownership in 2011.
Leicester City won the 2015–16 Premier League, their first top-level football championship. They are one of only six clubs to have won the Premier League since its inception in 1992. A number of newspapers described their title win as the greatest sporting shock ever, considering at the start of the season they were favourites to face relegation. Multiple bookmakers had never paid out at such long odds for any sport. As a result, the team was dubbed "The Unbelievables", a spin-off hearkening back to Arsenal's undefeated team "The Invincibles". The club's previous highest ever finish was second place in the top flight, in 1928–29, then known as Division One. Throughout Leicester's history, they have spent all but one season within the top two leagues of English football. They hold a joint-highest seven-second-tier titles (six Second Division and one Championship).
The club have been FA Cup finalists four times, in 1948–49, 1960–61, 1962–63 and 1968–69. This is a tournament record for the most defeats in the final without having won the competition. Leicester have several promotions to their name, two play-off final wins, and one League One title. In 1971, they won the FA Community Shield, and in 2016, they were runners-up. The club have also won the League Cup three times in 1964, 1997 and 2000, as well as being runners-up in 1965 and 1999. Additionally, Leicester City have competed in European football, with their appearances coming in the 1961–62 European Cup Winners' Cup, 1997–98 UEFA Cup, 2000–01 UEFA Cup, and most recently the 2016–17 UEFA Champions League, reaching the quarter-finals of the competition in that year.
Formed in 1884 by a group of old boys of Wyggeston School as "Leicester Fosse", the club joined The Football Association (FA) in 1890. Before moving to Filbert Street in 1891, the club played at five different grounds, including Victoria Park south-east of the city centre and the Belgrave Road Cycle and Cricket Ground. The club also joined the Midland League in 1891, and were elected to Division Two of the Football League in 1894 after finishing second. Leicester's first ever Football League game was a 4–3 defeat at Grimsby Town, with a first League win the following week, against Rotherham United at Filbert Street. The same season also saw the club's largest win to date, a 13–0 victory over Notts Olympic in an FA Cup qualifying game. In 1907–08 the club finished as Second Division runners-up, gaining promotion to the First Division, the highest level of English football. However, the club were relegated after a single season which included the club's record defeat, a 12–0 loss against Nottingham Forest.
In 1919, when League football resumed after World War I, Leicester Fosse ceased trading due to financial difficulties of which little is known. The club was reformed as "Leicester City Football Club", particularly appropriate as the borough of Leicester had recently been given city status. Following the name change, the club enjoyed moderate success in the 1920s; under the management of Peter Hodge, who left in May 1926 to be replaced two months later by Willie Orr, and with record goalscorer Arthur Chandler in the side, they won the Division Two title in 1924–25 and recorded their second-highest league finish in 1928–29 as runners-up by a single point to Sheffield Wednesday. However the 1930s saw a downturn in fortunes, with the club relegated in 1934–35 and, after promotion in 1936–37, another relegation in 1938–39 would see them finish the decade in Division Two.