Football League One is the second-highest division of the Football League and the third-highest division of the English league system.

Currently sponsored by Coca-Cola, the current format replaced the old Football League Second Division as part of a raft of rebranding measures introduced by League chairman Lord Mawhinney in 2004.

The third tier of English football was first introduced soon after the break in League football during the First World War.

A Third Division was added to the Football League for the 1920-21 season – won by Crystal Palace but after that one season, and with the addition of a wide geographical spread of new teams, the third level of League football was expanded and organised into two divisions on a North-South basis.

Following another reorganisation in 1958, an un-regionalised Third Division was created out of the top two halves of Division Three North and Division Three South, with the newly-created Division Four comprising the teams that had finished in the bottom halves of those divisions.

After the launch of the Premiership in 1992 the old Division Three became the new Division Two, which in turn changed its name in time for the 2004-05 season to League One, sitting one place below the newly-christened Championship.

At the end of each season the top two teams are automatically promoted to the Championship. They are joined by the winners of a play-off system that involves the teams that finished in third to sixth places, while the four teams who finish at the bottom of League One are relegated to League Two.