International School History - Skills - Sourcework -
The usefulness of historical sources

Private Sources
These are the key sources that make history different to journalism. Usually journalists do not have access to secret government and people's private communications.
Even in democracies, governments have strict control over information so that the business of government is conducted in secret. Discussions between government departments or between states remain secret for a fixed amount of time. In Britain for example this is 30 years. Only then are historians allowed into the archives to find out what was really said and done.
Strengths   Limitations
Diaries and government communication are often considered the most reliable of documents. They are the staple of traditional historical research. EH Carr famously described this fetishism of the documents in ‘What is History?’: ‘The documents were the Ark of the Covenant in the temple of facts. The reverent historian approached them with bowed head and spoke of them in awed tones. If you find it in the documents, it is so.’

The main value of these sources is that the people producing them know they can say or write what they like honestly, without concern for the views of others. Diarists for example need not concern themselves with what their relatives think. Politicians need not be concerned with what the voters might think. This is very liberating and often provides more reliable evidence about the past.

Occasionally wars or revolutions result in regime change that means previously secret information is suddenly made available.

The best example of this was the end of the Cold War in 1991 where communist regimes in Russia and Eastern Europe were overthrown. Almost overnight secret government documents were released covering decades of history behind the Iron Curtain. The significance of this was neatly summed-up by the title of the American Cold War historian John Lewis Gaddis’s 1997 book ‘We Now Know’. (see below)


  Writing down thoughts about a day’s events inevitably involves a process of narrative selection and construction that is simply one person’s version of events. Although, some diaries (especially by politicians) are written with the intention of publication in mind, even genuinely private diaries can present problems. History students are keen to make the legitimate point that diarists have no motivation to lie to themselves. But conscious lying is not the problem. Diarists are also prone to what social psychologists call ‘cognitive dissonance’ or what is commonly known as ‘sour grapes’. A classical example of this idea (and the origin of the expression ‘sour grapes’) is the Aesop’s fable The Fox and the Grapes. In the story, a fox sees some high-hanging grapes and wishes to eat them. When the fox is unable to think of a way to reach them, he surmises that the grapes are probably not worth eating because they are sour. Diaries are full of this post-hoc reasoning as diarists seek to explain their day in a meaningful way. It is not deliberate duplicity, but an inevitable consequence of human behaviour: we kid ourselves!

A second problem is the obvious lack of objectivity. In his analysis of the private papers of Gustav Stresemann the German statesman of the 1920s,EH Carr pointed out that what we have is always Stresemann’s version of events –
‘They depict Stresemann as having the lion's share of the conversations and reveal his arguments as invariably well put and cogent, while those of his partner are for the most part scanty, confused and unconvincing. This is a familiar characteristic of all records of diplomatic conversations. The documents do not tell us what happened, but only what Stresemann thought had happened, or what he wanted others to think, or perhaps what he wanted himself to think, had happened.’

A final weakness concerns the secret documents themselves. Just because documents have finally come down to us ‘declassified’, this doesn’t guarantee that they are complete and unexpurgated. Those that remain might come to us by chance or indeed as the result of deliberate selection. Wars, fires and regime changes can also lead to the destruction of documents in which the remaining sample can not provide a genuinely representative overview. This has been the case with documentary evidence of the Nazi regime in Germany for example which exists for very few German regions. (see below)

(above) Tape recorded, secret conversations between US Presidents and Secretary of Defense, Robert McNamara. Edited extract from the Errol Morris documentary 'The Fog of War'. They have since been declassified. (Above) Robert Gellately author of Backing Hitler: Consent and Coercion in Nazi Germany, 1933-1945, examines declassified Gestapo files to challenge the myth of 'Gestapo officers on every street corner'.
 President Reagan Speaking on the Telephone  
Ronald Reagan's telephone apology to Margaret Thatcher in 1983 was made public in 2014.  



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