The last known First World War combat veteran died in May 2011 and the last known First World War service veteran died in February 2012 (the year of writing). However, the remarkable collection of personal material acquired in the past forty-four years means that we are still in a position to gain the views of combatants of all ranks, via their personal papers and sound recordings. As a result, scholars are in danger of being spoiled for choice: while this collection contains the personal papers of a wide cross-section of First World War veterans, it represents but a fraction of the material that is available at the Imperial War Museum.
The reason for the wide range of material stems from the fact that the Great War represented the first occasion on which a truly mass British army was placed in the field, thus dramatically increasing the number of men in a position to record their experiences, and, more importantly, an army of soldiers who could record their thoughts on paper. The implementation of the 1870 Education Act meant that the soldiers of the First World War, if not particularly literary (a fact that shows in some of the archival material), were at least literate. Consequently, they were more likely to jot down their opinions than soldiers in previous wars and to send letters back to their families anxiously waiting for news at home. Thus, we are provided with material from across all of the services, not limited to specific rank or social class.
This does not mean, of course, that the plethora of material should be taken at face value. Memory is not infallible, and experience shows that a person's recollection of events even a few days after they occurred may not be exactly in accordance with the facts. We also need to take account of the fact that most soldiers writing home would be likely to disguise some of the more unpleasant realities of war from their loved ones, preferring generality to specifics in such circumstances; this factor can be seen vividly on occasion where the opportunity exists to compare letters home with private diary entries. Also, letters would face censorship, so some of the more interesting military details are often skimmed over. That said, 'the censor' was not just one man (who would have been fearfully overworked), but a collection of junior officers, some of whom would be more lenient than others in their consideration of what information could legitimately be sent home.
These diaries provide a far broader picture of the daily existence of the average British soldier than official records, and help to counter some of the deeply-ingrained perceptions about the nature of the Great War, and the supposed unending horror of daily existence. The whole issue of morale and relationships between officers and other ranks can be addressed through personal, as opposed to official, material. Some idea of the spirits of the troops can also be ascertained, although, given their scrutiny by a third party, letters are unlikely to be critical of officers or to speak of poor morale.
Such material has a further role to play, that of illuminating our understanding of how battles were fought, and how the men were trained to fight them. Taken in concert with other sources of evidence, personal experience sources, diaries, letters, postcards and photographs, provide us with a far greater understanding of how the First World War was fought, and the manner in which those fighting it lived, prepared for battle and went about their task than we could expect were we forced to rely upon the official records alone.