The translation of Gilfach Goch into English is easily understood (cil = nook or secluded area, bach = small) but several theories have been put forward as to where the name came from, especially the term coch = red.

[2] Writing in 1887, Thomas Morgan, put forward the idea that the name was derived from "...a heap of red cinders, which still remains as a memento of the ironworks that stood there in times of yore".

[4] These theories have been queried more recently, as it has been shown that the area known as Gilfach Goch and, in particular, the site where the red cinders of the ironworks are found, was not originally named as such.

[5] Gilfach Goch developed as coal mining village during the industrialisation of the south Wales valleys in the 19th century.

[7] At the south end of the village there are a series of parallel cul-de-sac properties lined with cottage pairs, not terraces which are synonymous to the region.

[7] In the 2001 census, of all rural areas with a population over 1,500, Gilfach Goch had the largest percentage of people in the whole of England and Wales who stated that they had no religion.

[8][9] The oldest building in the village is the Griffin Inn, a public house which is situated in low marshy ground at the end of a country lane.