I'm currently analysing the reliability of an extract of Halder's diary. I wanted to gather some extra context surrounding it so i know whether he was trying to be honest about his life, or whether he expected people to find it after his death (he would therefore shine himself in a good light). That is why I am wondering what purpose did he hope his diary would serve.
The usual caveats on human nature aside, Halder is reliable and useful primary source. It is clear from his diary that he did not intend for it to be read by his own generation – he frequently made incriminating comments about his peers (for instance, he clearly had little time for Guderian), as well as his superiors. One particular entry which stands out for me in this respect (only due to my recent interaction with it), was the period around 21 August 1941, when Hitler decided to change his mind regarding the focus for Operation Barbarossa. If Hitler had to read this section alone, he would not have appreciated Halder’s scheming with Brauchitsch.
When the going got tough, Halder had to hide his diary by burying it in a neighbour’s garden. It appears to me that he expected that his diary would never be read – that he would not survive his arrest and that the diary would be lost.
Of course, one could argue that Halder still wrote with one eye on history. Yet at the time, Germany’s star was very much on the rise. There was no way for Halder to anticipate the actual outcome of the war until much later. His diary can therefore be accepted as personal, possibly for a restricted audience at most. His entries are also, as one would expect, insightful and relevant for any analysis of the period. As a bonus, his observations are astute, and his own analyses reveal a razor-sharp mind.
Halder was a natural historian, as well as a working general. After World War II, he worked for the U.S. Army Historical Division. So he was a well-regarded historian, and his accounts (at least of facts) are more reliable than those of other German officers.
He was also imprisoned, but fortunately not killed, by Hitler, so he is also less suspect than the "Nazi" generals.