Evan Cotton was the Liberal MP for Finsbury East for only five months in 1918. He won a by-election caused by the death of Joseph Allen Baker in July that year, opposed by two candidates calling for boycotts of German goods after the war, whose supporters clashed during the contest. The Spectator reported: “Most of the voters fortunately kept their heads.”
After the First World War, Martin Archer-Shee defeated Cotton in the re-merged Finsbury seat. Archer-Shee had been the Tory MP for Finsbury Central since 1910. Cotton had been a member of the Calcutta corporation and a Progressive on the London county council (also for Finsbury East), writing histories of the capital of Bengal and the East India Company.
After his defeat, he returned to India and served on the Bengal legislative council.