Formed in September 1920 with the amalgamation of the Stratford Co-operative Society and the Edmonton Co-operative Society, with other societies jouing thereafter.
It amalgamated with the Co-operative Retail Society in 1981.
The archives are at the Bishopsgate Institute - details can be found here and here.
The Wikipedia page is [1], which itself merged with the larger Co-operative Wholesale Society, to form the Co-operative Group (CWS) Ltd.).in 2000