Hey! My way of handling the large amount of content was writing up brief dot-point notes of really important facts and details. Dates are actually very important, as when you are writing your essay and you put in the wrong dates, it can be confusing for the marker. At the end of the day, it's really all about putting all the information that you have gained into an essay. So my advice would be: write up some notes, and practice writing essays!
Hope that helps, and thanks for the bump!