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 and maps chiefly concerning the Fife and Forfar Yeomanry, [1918]-1959, including typescript copy of war diary, 1 Armoured Reconnaissance Bde, British Expeditionary Force (BEF), Belgium and France, 30 Mar-30 May 1940, with typescript recommendations for awards, 1940; typescript account, dated Jun 1942, of dispositions and operations of B Sqn, 1 Fife and Forfar Yeomanry, Belgium and France, 14 May-1 Jun 1940; typescript list entitled '1 Fife and Forfar Yeomanry, nominal roll of casualties sustained in France, 1940'; article by Maj Otho Munton Bullivant, Adjutant, 1 Fife and Forfar Yeomanry, entitled 'With the BEF [British Expeditionary Force] in Flanders', from The Tank [1941]; typescript 'Precis of activities of 1st Fife and Forfar Yeomanry', British Liberation Army, North West Europe, Oct 1944-Feb 1945, and 'Details of activities of 1st Fife and Forfar Yeomanry', 1-31 Mar 1945; correspondence with various officers concerning Regimental affairs, 1943-1945, including Col James Younger, 2nd Viscount Younger of Leckie, Honorary Col, Fife and Forfar Yeomanry, 1945; correspondence, dated 1944-1945, relating to the return of the Regimental band instruments, abandoned by the Fife and Forfar Yeomanry during the retreat to Dunkirk, 1940, and kept by the local townspeople, France, 1940-1944; official correspondence concerning Prain's Army pension and war disablement compensation, 1946-1956; correspondence, dated 1947-1959, relating to the writing and publication of The Fife and Forfar Yeomanry, 1919-1956 by Robert James Batchen Sellar (William Blackwood, Edinburgh and London, 1960). Twenty five photographs relating to the Fife and Forfar Yeomanry, 1923-1945, including group photograph of Armoured Car Company, Fife and Forfar Yeomanry, Annesmuir camp, Scotland, Jul 1923; five photographs of Fife and Forfar Yeomanry Vickers Light Tanks Mark VIB and Universal carriers, France, 1940; official photograph of Infantry Tank Mark IV Churchill Crocodile flame-throwing tank, storming of the Senio river, Italy, Apr 1945.