His father was Daniel Thomas, owner of the lime kilns at Llandough and a contractor with offices in Grangetown, Cardiff).
[1] He was educated at Weston School, near Bath, but he decided not to pursue a university career to join his father's business.
[1] Early in his business career, Thomas was involved with the construction of the Rhondda Fach branch of the Taff Vale Railway.
Thomas had also studied for a short time as a lay student at Regent's Park College under Joseph Angus.
[1] As mayor he was central to the decision to locate the University College of South Wales and Monmouthshire in Cardiff, rather than Swansea.
He gave £1,000 towards the building fund and the decision to locate the university at Cardiff was announced before the end of his term as Mayor.
[3] Shortly afterwards, Thomas emerged as a leading contender for the Liberal nomination in East Glamorganshire, and after several months of campaigning he saw off the challenge of his main rival, Bowen Rowlands.
He was knighted in the 1902 Coronation Honours,[6] receiving the accolade from King Edward VII at Buckingham Palace on 24 October that year.