Locke on Personal Identity

Sorry if this is a dumb question, I'm a uni student trying to wrap my mind around this lol. If personal identity for Locke is a matter of continuity or a condition of the memory, where the relation between stretches of consciousness that makes them these "person stages" of a single person is that one later in time contains memories of the one prior, or as he puts it we "extend our consciousness back to time." Or simply if its the relation between memory and the individual to be the source of identity, then what would Locke say in response to the problem of duplication? If you were to duplicate the brain of person A and place that brain in person B since person B has all the same memory states as person A, is person A person B to Locke? Why or why not?
Additionally (the dumb part)- what if I were to get really into reading Napoleon, I read all of his books enough that I could remember certain facts about his experiences, and then in some ways have some memory of what it was like to fight battles and such, how does Locke avoid saying that I'm not Napoleon in this case?