As a historical novelist myself, I face that question all the time. I can't offer any specific guidance except to say that I prefer not to see an authorial hand pulling the strings. The writers of historical fiction I admire create characters who struggle with what's going on around them (even if that struggle sometimes takes the form of trying to ignore it, inevitably in vain). Historical detail works best when it pervades daily life, and the character has decisions to make accordingly, whether momentous or mundane, not when the author blatantly supplies or withholds it. I think this is particulary crucial in your example, Diviner, because the reader already knows more or less how things will turn out. The tension will come from empathy with the main character and the desire to see him or her face circumstances, if not to triumph, then at least to put up a spirited resistance and rise above the ordinary.
As for setting the scene initially, as everyone's saying, you have to strike a balance. The reader can't know everything at once but shouldn't be misled, either. To me, giving a firm grounding in time and place matters most immediately; the relevant facts can come gradually.
