What was involved in the leagues in 1920's

The Football League Third Division was introduced, in effect the Third Division South of the following season, when Third Division North was introduced. This expanded the League's operational radius all the way to the south coast of England, as the number of member clubs increased from 44 to 66.

Team changes. The new Third Division was formed by clubs of the Southern Football League Division One of the previous season, except for Cardiff City. Cardiff City became the first Welsh club to enter the League, and since they were the strongest club in Wales in the era, they were invited directly into the Second Division. Grimsby Town took its place in the new Third Division, thereby being the first club relegated to the League's third tier. Leeds United were also elected into the Second Division to replace Leeds City after its debacle. Lincoln City were not re-elected to the Second Division and thus Port Vale's Second Division place was formalized as well.

Final league tables. Beginning with the season 1894–95, clubs finishing level on points were separated according to goal average (goals scored divided by goals conceded), or more properly put, goal ratio. In case one or more teams had the same goal difference, this system favoured those teams who had scored fewer goals. The goal average system was eventually scrapped beginning with the 1976–77 season. From the 1894–95 season and until the 1920–21 season the re-election process was required of the clubs which finished in the bottom three of the league.[2]

References. "England 1920-21". Rec.Sport.Soccer Statistics Foundation. Archived from the original on 5 February 2010. Retrieved 24 February 2010.
^ a b Ian Laschke: Rothmans Book of Football League Records 1888–89 to 1978–79. Macdonald and Jane’s, London & Sydney, 1980.
^ a b c "English League Leading Goalscorers". RSSSF. Retrieved 31 October 2010.
^ "Season 1920–21". English Football League Tables. Retrieved 28 March 2019.
Ian Laschke: Rothmans Book of Football League Records 1888–89 to 1978–79. Macdonald and Jane’s, London & Sydney, 1980.

hope it helps ps have a great day:) (taken from Google)

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