In 1870 Morgan took on a job as a writer on the Western Mail, and around the same period he began to write his own books after taking an interest in local history. He made his name as a journalistic writer when he covered the Tynewydd Colliery rescue in Porth in 1877. Morgan closely *ociated himself with Myfyr Morganwg (Evan Davies), a self-proclaimed archdruid and Welsh writer in neo-druidry, who himself was a student of Iolo Morganwg (Edward Williams) one of the most important and controversial historians in Welsh affairs. In 1889 Morgan published Pabell Dafydd, a Welsh language book on druidism which he followed with Kimmerian Discoveries, covering Morgan's research and thinking on the alleged Chaldean origins of the Welsh people. In 1893 he wrote his magnum opus The Light of Britannia which again explored Druidism in Britain, but also included chapters on phallic worship, King Arthur and his twelve knights and Saint Paul's supposed journey to South Wales. In 1901 Morgan released, The Royal Winged Son of Stonehenge and Avebury a reprint of Kimmerian Discoveries under a different *le. The Royal Winged Son was republished in 1984 under the *le Mabin of the Mabinogion.
Other books written by Morgan include A Guide to the Gorsedd (n.d.) and a 1903 publication, A History of Pontypridd and the Rhondda Valleys, the latter was described by Welsh historian Robert Thomas Jenkins as "an odd jumble of Druidism, mythology, topography, local history and biography". Paul R. Davis in his 1989 publication Historic Rhondda, goes further, blaming the book for misleading future historians, giving one example concerning Ynysgrug, a motte and bailey castle once located in Tonypandy: Morgan not only misidentifies the height of the 30:ft. mound as 100:ft. but states that "...all these sacred mounds were reared in this country...when Druidism was the established religion", but gives no historic proof. A History of Pontypridd and the Rhondda Valleys also contained an illustration of Ynysgrug, to which the artist has added a moat and several druids, neither of which are factual. Despite Morgan's spurious research into Welsh history, this final book has become worthy of some note due to its account of 19th century life in the industrial valleys, the time from which he was writing.