During his life he donated substantial sums to the Nonconformist denominations and to the Church in Wales to improve the stipends and pensions of ministers, to St. David's College, Lampeter, to Pontrhydfendigaid village and to numerous other causes. In 1952 he founded the Pantyfedwen Trust which was administered from London. Its purpose was to promote religious, educational and charitable causes in Wales. This was abolished in 1957 when he founded the Cathryn and Lady Grace James Trust (named after his mother and his wife). In 1967 he founded a second Trust in the name of John (his father) and Rhys Thomas James (his brother who died young). Late in the 1950s Pantyfedwen Eisteddfodau were established in Pontrhydfendigaid (The James Family Eisteddfod), Cardigan (John James Memorial Eisteddfod) and Lampeter (Rhys Thomas James Eisteddfod). Sir D.J. James's main aim was to give individuals an opportunity to compete in eisteddfodau intermediate in standard between those of local eisteddfodau and the national eisteddfod. He participated in transferring the administration of the trusts to Aberystwyth but d. before the official opening of the Trusts’ offices there in 1968.
He received an hon. LL.D. degree of the University of Wales in 1957, was knighted in 1959, became a member of the Order of the White Robe of the Gorsedd in 1965, and the following year he was granted the freedom of the borough of Aberystwyth.
His wife d. 20 Feb. 1963 and he d. 7 Mar. 1967 and they were buried in Strata Florida cemetery.
Richard Harding Morgan, Aberystwyth