supporter of Dafydd Wigley's leadership and resisted the challenges against Wigley. Despite his strong convictions that Plaid Cymru had made a mistake in losing Wigley as party leader, Thomas remained loyal to the party whip and its new leader Ieuan Wyn Jones. Thomas faced a strong challenge for the 2003 regional seat selection, but comfortably won the membership vote. A strong supporter of the Welsh language and Welsh history, he wrote in the Western Mail that "The language is a national asset and its revitalisation can play a central part in the larger process of nation building and economic and social regeneration." He also complained that Welsh children are taught "the history of England, not the history of Britain". His proudest achievements as an AM include an unsuccessful campaign to have St David's Day recognised as a bank holiday, his role in the creation of the Wales Millennium Centre, his campaigns for the Allied Steel and Wire pension fund, and to bring brachytherapy, a cancer treatment, to Wales. Thomas was the Plaid Cymru candidate for the Cathays ward in the May 2008 Cardiff local elections, increasing the vote and receiving the highest vote that Plaid Cymru has achieved in that ward. He also ran for that ward in the 1983 local election. Later life Following retirement at the age of 67, Thomas remained active within Plaid Cymru, serving as the party's chair in Cardiff Central and in Cardiff. He is the longest serving trustee of Tŷ'r Cymry, a house given to the Welsh speakers of Cardiff in 1936. In November 2020, his book, The Welsh Language in Cardiff : A History of Survival was published by Y Lolfa. The book is an attack on the myth that Cardiff has been an English speaking town since the Anglo-Norman conquest of Cardiff in 1100, emphasising instead that a very significant element of its population have been Welsh speaking throughout history. Personal life Thomas has been married to Siân Wyn Evans, a former headteacher of Ysgol Glan Morfa, Splott, since 1985. The couple have twin sons. Thomas has three sons and a daughter from a previous marriage. His youngest son, Rhys ab Owen, also a Plaid Cymru politician, was elected on the South Wales Central regional list in the 2021 Senedd election, the same seat Thomas had represented fourteen years earlier. Another son, Rhodri ab Owen, is the Chief Executive of the Cardiff