Significant settlement at Cwmcarn came with Bronze Age migration of local tribes from the Gwent levels to the uplands of Mynydd y Grug, Mynydd Machen and Mynydd Maen (Twmbarlwm) and led to a later Iron Age (900-55 BC) hill fort to be constructed by the Silures on Twmbarlwm.
The name of Cwmcarn came about in 942 when Llywarch ap Cadogan gave Villa Treficarn Pont (estate near the bridge over the Carn) to Bishop Wulfrith with King Cadell's guarantee i.e the place where the Carn meets the Ebbw (now Cwmcarn).
Following the Norman invasion of Wales the separate townships of Abercarn, Cwmcarn and Newbridge were given a manorial title of Abercarne. The three townships were also within the boundaries of the ancient parish of Mynyddislwyn and remained therein up until comparatively recent times.
Cwmcarn lies at the south-eastern edge of the South Wales coalfield. The Cwmcarn Colliery development started in 1836 as a single 180ft downshaft for the nearby Prince of Wales Colliery at Abercarn operated by the Monmouthshire Iron and Coal Company.
The Cwmcarn Forest Drive now runs over the shafts of the colliery and a relics of colliery buildings can still be seen on the slope above the old shaft. The present day lake that is stocked by the Cwmcarn Angling Association was originally down stream of the colliery's washery.
The Iron Age hill fort of Twmbarlwm, was at the heart of the territory of the Silurian Celts, the dominant Celtic tribe of South East Wales.
The story of Prince Madoc inspired John Evans to set off to find a tribe of First National Americans whom he was sure would be speaking Welsh.
At it’s peak Cwmcarn Colliery employed 700 men yielding 1,000 tons of coal per day.