Rhondda East was for a time a heartland of the Communist Party of Great Britain, who formed the main opposition on the council.
For a time, Annie Powell was the only Communist mayor in Britain.
Harry Pollitt, General Secretary of the CPGB, narrowly failed to win the seat in 1945.
1918–1949: The Urban District of Rhondda seventh, eighth, ninth, and tenth wards, and part of the sixth.
1950–1974: The Urban District of Rhondda seventh, eighth, ninth, tenth, and eleventh wards, and part of the sixth.