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During the 1950s the club changed leagues several times; they were members of the Delphian League between 1951–52 and 1954–55, rejoined the London League in 1955 and then left to become founder members of the Aetolian League in 1959.
The Isthmian League was most likely named after the ancient Isthmian Games, with the later Athenian League, Corinthian League and Delphian League all adding a Classical flavour to amateur football competition.