Football League Division Three South

The Third Division South of The Football League was a tier in the English association football league system from 1921 to 1958. It ran in parallel with the Third Division North with clubs elected to the League or relegated from Division Two allocated to one or the other according to geographical position. Some clubs in the English Midlands shuttled between the Third Division South and the Third Division North according to the composition of the two leagues in any one season.

The division was created in 1921 from the Third Division, formed one year earlier when the Football League absorbed the leading clubs from the Southern League.

In 1921 a Northern section was created, and the original division was renamed Third Division South. The original 22 teams in the Third Division formed the new Third Division South, with the exceptions of Crystal Palace, who were promoted to the Second Division, Grimsby Town who were transferred to the Third Division North, and Aberdare Athletic and Charlton Athletic who joined The Football League for the first time. Several Midlands-based teams were included in the Third Division South from time to time, although most were geographically closer to their Northern division rivals; Nottingham Forest and Notts County played in the Southern division although nearby Derby County spent time in the Northern division.

For the 1950-51 season the division was expanded to 24 clubs, with Colchester United and Gillingham joining.

Only one promotion place was available each season from the Third Division South to the Second Division, which made it very difficult to win promotion. Six teams, Brighton & Hove Albion, Exeter City, Northampton Town, Southend United, Swindon Town, and Watford, were ever-present in the division for the 30 years of its existence. Of the teams that played in the Third Division South, Portsmouth, Ipswich Town, and Nottingham Forest were later English football champions.

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