Papers relating to his military career, 1944-1952, dated [1944-1953], [1960-1980], comprising account of advance of 2 Bn, Essex Regt through Northern France and Belgium, June-Oct 1944, notably covering the attack on Le Havre, 10 Sep 1944, written in [1945], with appendix dated [1960-1980]; account of withdrawal of 2 Infantry Bde from Belgium and Northern France, May 1940,culminating in their evacuation from Dunkirk on 1 Jun 1940, written in [1944-1945]; notes on the allotment and loading of vehicles, Operation OVERLORD, June 1944; map of German defences at Le Havre, issued by [the War Office], 1944; map showing position of 51 and 49 Div to the north of Le Havre, 7 Jun 1944, issued by the War Office, 1947; two accounts of the work of 1 Bn, The Queen's Own Royal West Kent Regt, in Malaya, 1952, written in [1953].

The collection consists of pamphlets written by Davidson, papers relating to his part in the Allied Military Mission to Moscow, USSR, 1939 and papers relating to his career in World War Two as Commander in the Royal Artillery and as Director of Military Intelligence. The World War Two material includes maps used in the retreat of the BEF (British Expeditionary Force) to Dunkirk, France, maps used as Director of Military Intelligence to illustrate the progress of the war to Queen Mary, mother of George VI and a personal diary kept while Director of Military Intelligence. There is also a file containing correspondence with E E Thomas of the Cabinet Office Historical Section relating to aspects of Military Intelligence during World War Two.

Papers including maps, relating to operations of British Expeditionary Force in France and Belgium, 1940-1941; Staff College study of Italian campaign, 1915; papers including those by Maj Gen G M Lindsay relating to armoured support for 7 Infantry Brigade, 1933-1934; appendix, including maps of Britain annotated for exercises including SPARTAN, 1943; correspondence dated 1977-1978 with Martin Alexander of St Antony's College, Oxford including Franco-British military relations, 1939-1940; notes of conversation in 1975 with Dr A W J Houghton relating to the evacuation of Dunkirk, 1940.