The original correspondence of Robert Monckton is contained in one volume and, while it covers the period 1751-83, the greatest number of letters concern events in North America and Canada, 1755-1763. Many are from the most influential men engaged in the war with France at that time, including General James Abercromby, William Pitt and Major General James Wolfe. There is also a section containing photocopies of personal letters from Robert Monckton to his brother Jack, dated 1762-1763. The originals of these are in the National Archives of Canada.
There is little material concerning Monckton's life after his return to Berwick.