Records of the Herbert family of Montgomery, Chirbury and Powis Castle, later earls of Powis, 13-20 cent., including records of the Powis Castle estate, including title deeds, mainly in Montgomeryshire and adjacent counties, notably Shropshire, 13-20 cent.; records of lead and silver mining in Cardiganshire, 18-19 cent.; records of the Castle Island estate, County Kerry, Ireland, 16-19 cent.; manorial records for the barony of Powis from 1549, the lordship of Oswestry from 1577, the manors of Cydewain, Halcetor and Montgomery from 1525, Chirbury from 1373, Pool from 1653, the borough of Llanfyllin from 1653, and many others; records of the borough of Llanfyllin, 1674-1820 including records of the Court of Record (borough court), 1674-1721, 1761-1763; estate rentals, 1712-1941; rentals of chief rents, 1676, 1745-1897 (mainly 1745-1817); correspondence, mainly 17-19 cent.; Montgomeryshire Chartist riots papers, and papers relating to the campaign against the proposed union of the dioceses of St Asaph and Bangor. Manuscripts and papers of Edward Herbert, 1st baron Herbert of Chirbury (1583-1648); Robert Clive, 1st Baron Clive (1725-1774) and Brigadier-General John Carnac (c.1716-1800) have been removed from the archive and catalogued as separate collections.