The video seems to be something on the entire world, or at least a large section of time. In the instance of some info overlapping with what was covered in History of Japan, will you skip over it or do something new for that info? I don't imagine you'd just reuse direct footage from the HoJ vid.
it's all new, although you will recognize the plot points. plus as a bonus in this video  i have also included japan's worst plot point, by popular demand