Mold was the site of a Norman motte and bailey castle and the town grew up around this feature on Bailey Hill.
The Welsh name for Mold, Yr Wyddgrug, is derived from the Yr gwydd crug (tomb on the mound) and the English version from the Norman-French mont-hault, meaning high hill. The castle was the site of many battles between English and Welsh forces. Owain Gwynedd captured the town for the Welsh in 1144, and they won battles over the English in 1201 and 1322. The last Norman lord died in 1329 and the castle changed ownership frequently thereafter. The nearby Maes Garmon (field of Germanus) was the site of the British Alleluia Victory over the Picts and Scots which was led by Germanus of Auxerre in 430 AD.
The first church in Mold was built by the Montalt family in the twelfth or thirteenth century and is recorded in 1253. Margaret Beaufort (Countess of Richmond) built the present church to celebrate the victory of her son, Henry Tudor, at the Battle of Bosworth. She had married Thomas Stanley (Lord of Mold) three years earlier which provided the Mold connection. Lord Stanley was rewarded for his efforts at the Battle of Bosworth with the Earldom of Derby. As a result, he and Margaret endowed colleges at Oxford and Cambridge and rebuilt several churches (including Mold, Gresford, Northop, Wrexham and Holywell in North Wales) in thanks for their favoured position. The church was slowly rebuilt over the subsequent centuries as sufficient money became available.
Mold established two annual fairs from the fifteenth century and the mayor of Chester was captured in 1465 while attending one of these events. He was taken to Nercwys and hanged which resulted in a skirmish between the English and Welsh. Apart from the Civil War, the town's history was more peaceful in Tudor times. Its coalfields started to attract people to the town in the nineteenth century and its population doubled. However, the town's services failed to keep pace with the rate of change and this resulted in riots over poor living conditions and wages.
In 1869 John Young, the English manager of the nearby Leeswood Green colliery, angered his workers by announcing a pay cut. He was already unpopular because of a ban on speaking the Welsh language underground. Two days later, the miners attacked Young and took him to the police station. Seven men were arrested for the and found guilty, with the alleged ringleaders, Ismael Jones and John Jones, being sentenced to a month's hard labour. A large crowd assembled to hear the verdict, and the Chief Constable of Flintshire had arranged for policemen from all over the county,and soldiers from Chester to be present. As the convicts were being transported to the railway station, the crowd grew restive and threw missiles at the officers. The soldiers opened fire on the crowd, killing four people . Although he denied the connection, Mold writer Daniel Owen's first novel, Rhys Lewis, was based on these events.
In 1833 a Bronze Age golden cape was found at Bryn yr Ellyllon (Fairies' Hill) dating from 1900-1600 BC. It weighs 560g, was made from a single gold ingot and is now on display at the British Museum. Mold hosted the National Eisteddfod in 1923, 1991 and 2007, plus an unofficial version in 1873. The town's railway links were severed in the 1960s although a branch survived for another decade to the Synthite works.
Mold's current attractions include Clwyd Theatr Cymru, the Grade I listed Church of St Mary the Virgin and the museum. The town's population at the last census in 2001 was 9,568.