Chelsea Football Club was established in 1905 and the club has played in their Stamford Bridge stadium, in Fulham, London since their foundation. The club currently competes in English football's top tier, the Premier League, and is widely known as Chelsea or The Blues.

Chelsea won its first major honors in the 1950s but their most successful period has been the last two decades where they have won 15 major titles, including a Champions League, Europa League, three of their four league titles and five of their seven FA Cups. In July 2003, the club was bought by Russian billionaire Roman Abramovic in a deal worth about £140 million and the club has continued rising in status and popularity ever since, attracting big-money signings and being, regularly, among the top spenders in the Premier League. In 2012, the Blues would become the first London club to win the Champions League and, one year later, the only British club that won all three main UEFA competitions (Champions League, Europa League and UEFA Cup Winners' Cup). In 2014, Chelsea was considered the sixth most valuable football club in the world, valued at £560 million.

Chelsea is one of the most popular clubs in the world, with the fifth highest overall attendance in English football and were ranked fourth worldwide in kit sales between 2007 and 2012. Chelsea's global profile has seen the club feature in several films or TV shows around the world, such as The Great Game, released in 1930, a Bollywood Hindi film, Jhoom Barabar Johm, or a comedy series from Montenegro. The club was also mentioned in Alfred Hitchcock's film The 39 Steps and saw famous fan Bryan Adams release a song about the club, entitled "We´re Gonna Win".

The Blues' female football team, Chelsea Ladies, was one of the eight founders of the FA Women's Super League in 2010. The iconic and current captain of the male Chelsea football team, John Terry, is the President of Chelsea Ladies.

The club's main rivalries are with Arsenal, Tottenham and Manchester United. Their West London neighbors, Fulham and Queens Park Rangers don't have the consistency and dimension to form an intense derby rivalry.