Thomas was born in November 1832 at Llanfihangel Genau'r Glyn, Cardiganshire, Wales to Thomas Thomas, carrier, and his wife Mary. At age nine he was working at a woolen factory and at fifteen was employed in the lead-mines of Esgair and Bwlch Gwyn. He moved on to working in the coal and iron mines of South Wales and in 1859 he set off to Australia. Landing in Victoria, he worked as a gold miner but was unsuccessful and relocated to Queensland some two years later where he turned to coal mining in the West Moreton district. This time his venture was such a success that he opened up many of the coalfields in the area and with the building of railways across Queensland the demand for coal become even greater, earning him a vast fortune and eventually became known as the 'Coal King'. In 1890, Thomas retired from mining and handed over the business to his employees, who formed the Aberdare Co-Operative Coal Co. Ltd.
In 1859, Thomas married Ann Morris at Llanfihangel Genau'r Glyn and together had 1 daughter, Mary, who grew up to marry Thomas Cribb Jr., the son of Thomas Bridson Cribb, the then Treasurer of Queensland. He had a great love of music, and for many years sponsored the annual Queensland Eisteddfodau, to which he gave between £60 to £100 to the chief choral contest. He was also patron of the Blackstone-Ipswich Cambria Choir and was often seen at the festivals in which they competed. Thomas was a trustee of the Ipswich Girls' Grammar School and also donated the annual 'Thomas Lewis Scholatship' to the boys Grammar School. Around 1905, Lewis was on a tour back to Wales, and while there he donated £1000 to establish a scholarship at the Aberystwyth University. In 1890, Thomas built 'Brynhyfryd Mansion' at Blackstone. It was an elaborate home, three stories high and containing 49 rooms including a basement and a tower. It was built on top of a rich coal seam, and while Thomas was alive, refused to mine the coal as it would mean having to demolish his home. After his death his wife, daughter, and her husband continued to live there and it was eventually sold in 1934 to Rylance Collieries and Brickworks who demolished the mansion in 1937 to mine the coal deposits below. Thomas died in February 1913, and his funeral proceeded from his home in Blackstone to the Ipswich General Cemetery.
