While doing your historical research in an archive, you might find a collection with a diary in it.
Not to be discouraging but proceed with caution!
A lot of the diaries that end up in archives aren’t the juicy, detailed, scandalous, social historical documents you read about in Jane Austen.
Instead, a lot of them are rather simple weather reports or statistical data tracking miles traveled in a day stops along a route, or something like that. Could still be useful of course.
Just warning you 🙂