This is not a good show and Netflix shoukd drop it immediately. I am no expert but some of the facts seem to be very questionable. Dates where major events happened etc. There are some respected historians commentating on this show bit I would.imagine if they looked back, they would be very annoyed at how the final cut of the show was presented.
Also, the footage and commentary is repeated at nauseum to try and drag this out over 4 episodes. It could have easily been all condensed into a single 1 hour show without losing any information theybare trying to get across.
Not in the same league as World War 2 in Colour.
Don't bother watching it.