So this doesn't directly answer the question but for history making a timeline for key events might be useful - helps you see the order in which things come in (which can be useful if you can't remember an exact date for something, as you know roughly what happened before/after/at the same time) as well as helping you remember the dates.
That said, it's fairly similar to a mindmap in that it's a lot to take in at once and it depends on how best you learn. To learn dates, it's probably most useful used alongside revision cards.
In the case of mindmaps/timelines/other poster type things, it's generally best to make them big and colourful and then stick them on your wall somewhere, so you can look at it on a regular basis. Just helps it all go in.
Or does it play no part?