 The Rhondda also has a strong history of communist sympathy , with the Rhondda Socialist Society being a key element in the coalition that founded the Communist Party of Great Britain . By 1936 there were seven Communists on the Rhondda Urban District Council and was publishing its own Communist newspaper The Vanguard . In the 1930s Maerdy became such a hotspot of Communist support it was known as Little Moscow producing left wing activists such as Merthyr born Arthur Horner and Marxist writer Lewis Jones . The Rhondda miners were also active in socialist activities outside the valleys . In the 1920s and 1930s the Rhondda and the surrounding valleys provided the principal support of some of the largest hunger marches , while in 1936 more Rhondda Federation members were serving in Spain as part of the International Brigades than the total number of volunteers from all the English coalfields . 
