Papers relating to the administration of the Plas Power estate and household, including some properties belonging to the Chirk estate, some but not all of which became part of the Plas Power estate; also included are some records from other properties in England that were owned by the Myddelton family.
Personal and private papers of the Myddelton, Lloyd and FitzHugh families and their households, together with papers accumulated by them in the course of their public activities.
Letters, including copies and drafts of letters, to members of the Lloyd and Myddelton families and households at or concerning both Plas Power and Chirk, together with some addressed to members of the Fownes family, relating to administrative, legal and financial estate and household business, as well as family and personal matters, with occasional references to politics. While the relationship of some recipients to either Plas Power or Chirk is clear, there are many cases where it is complicated or unclear. From 1720, Plas Power was rented by Rev. Thomas Lloyd, who was the sitting tenant there until his death in the following year. Meanwhile, Mary Myddelton left Chirk Castle in 1719 and rented Croes Newydd, where she lived for the rest of her life, despite purchasing Plas Power in 1733. In 1734, Thomas Lloyd was succeeded as the tenant at Plas Power by his son, William, to whom Mary Myddelton bequeathed the estate on her death in 1747.
Papers relating to the activities of the Myddelton, Lloyd and FitzHugh families in public office. Several members of the Myddelton family held office as Deputy Lieutenants of Denbighshire.