There never really is a fixed requirement.
Most of them ask for a Level 5 in English.
Otherwise, they expect atleast one essay writing subject (and your EE as an essay writing subject).
My choices were:
EE was in Geography.
As you can see, you don't really need to choose IB Higher English, (I got into Warwick btw).
There is no MUST for history, but if a university (like you said Cambridge) asks for it, you might aswell choose it. My IB advisor/coordinator advised me to choose a subject for my EE which allowed me to write in essay style rather than experimental/report style. So I did my EE in human geography.
BUT, some subjects can help you set up to the law style of learning, higher english, maths, and sciences help with rational thought etc., but shouldn't really give any form of advantage at all, everyone is taught the same thing on the same level.
Remember, if a University asks for specific subjects, take it. Otherwise choose anything, there is a reason why many IB students apply for Law.