Mansel was elected Member of Parliament for Glamorgan in 1679 (twice) and again in 1689, 1690, 1695, and 1698. He had m. 17 April 1646, Catherine, daughter of Hugh Perry and widow of Sir Edward Stradling of S. Donat's castle, Glamorgan. (Catherine must have been his first wife; see below).
Some of Bussy's correspondence for the period 1670-95 is preserved among the Penrice and Margam muniments; the references are L 104a and b, 126, 149, 190, 206, 224, 228-9, 232-5, 238, 240-2, 244, 260, 263, 293-5. L 104 (14 and 15 Feb. 1669/70) refers to the working of a coal mine. L 149 shows that Bussy had m., as his second wife, an Anne, to whom he writes on 5 May 1678, requesting her to pay Sir Edward Mansell the sum of £62 ls. 6d., ‘Sir Edward haveing allready disbursed soe much for me to my souldiers …’ L 190 (16 Aug. 1687) is a letter to him about timber bought of Sir Humphrey Mackworth, L 224, dated 5 April 1691, refers to the impressment of seamen. In some of the letters, many of which are addressed to his kinsman, Sir Edward Mansel, bart., Bussy gives parliamentary and other news from London.
Bussy Mansel d. in May 1699 (buried at Briton Ferry 25 May 1699 — his will is dated 30 March 1699), leaving as his heir his grandson THOMAS MANSEL (Clark, Cartae, vi, 2250), who, on his death in 1706, was succeeded in the ownership of the Briton Ferry estate by BUSSY, 4th baron Mansel, who m. (2) lady Barbara, daughter of William, 2nd earl of Jersey.
Sir William Llewelyn Davies, M.A., LL.D., F.S.A. (1887-1952), Aberystwyth