The British Legion was formed on 15 May 1921, bringing together four national organisations of ex-Servicemen that had established themselves after the First World War:
The National Association of Discharged Sailors and Soldiers
The British National Federation of Discharged and Demobilized Sailors and Soldiers
The Comrades of The Great War
The Officers' Association
https://en.wikipedia.org/wiki/The_Royal_British_Legion
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