The development of the village can be attributed largely to the coal seams of north-east Wales that pass near it. The burgesses of Holt were granted the right to dig for coal at Rhos in their borough charter of 1563. A coal mining community was established during the 18th century, and grew substantially from the 1840s onwards. Unlike many other mining villages in the district and in other parts of Wales, the majority of early immigration to Rhos was from Welsh-speaking upland agricultural areas in West Wales, giving the village a distinct linguistic identity which it has retained until the present day. The proportion of Welsh-speakers in Rhos did not fall below 50% until the time of the 1981 census.