The Shirley papers comprise around 20,000 volumes and documents relating to the estate and local political affairs of the Shirley family of Lough Fea, Carrickmacross, Co. Monaghan (and Ettington Park, Stratford-upon Avon, Warwickshire).
What PRONI holds is essentially an estate archive, documenting the history and management of the Shirley estate, with an area of some 40 square miles, in the western half of the barony of Farney, Co. Monaghan, in the period 1576-1960. Other papers derive from the historical, antiquarian and genealogical pursuits of Evelyn Philip Shirley (1812-1882). Scholars are fortunate in having in published form the results of E.P. Shirley's researches in his books, Some Account of the Territory and Dominion of Farney in the Province and Earldom of Ulster, 1845 and The History of the County of Monaghan, 1877-1878, a copy of the latter is available in the PRONI library.
The great concentration of the Shirley archive is in the century between 1830 and 1930. This makes it of great interest, not least because the geographical concentration of the estate makes it an ideal focus for a socio-economic case study. This is especially true in relation to the part of the 19th century for which the records are particularly detailed. They yield much information on a period when Monaghan was the cockpit of much that was going on in Ireland in terms of the inter-related questions of land and politics.