[Update: I originally had one character spelled 'Sussman', which is as I heard it phonetically in the presentation, but the livestream revealed it's actually 'Zussman'.]
Now, this is currently conjecture with nothing confirmed by Activision but the names and details line up so precisely that it's hard to ignore.
Firstly we have Zussman, a soldier in the 1st Infantry Division and one of the main characters. Sledgehammer's Michael Condrey described him to me in the following way:
"Zussman is an American, a Jewish American fighting in Germany, and he becomes captured and I won’t tell you the rest of the story because we want the fans to see it, but you can imagine there are some really personal, harrowing moments of the two of them as they grow as humans and they mature through the war."
There is actually a Charles I. Sussman listed in the Prisoner of War records (opens in new tab) who was captured and taken to Stalag 7A, a POW camp near Moosburg in Germany. He's also the father of Rabbi Lance Jonathan Sussman, whose wiki page (opens in new tab) mentioned Charles received "a bronze star and other decorations for valour during World War 2." What are the odds that Red, his friend and other main playable character, ends up rescuing Zussman from the camp, providing a very dramatic narrative beat.
The other character that seems to have a very real basis is Rousseau. According to Condrey, "you’ll play as Rousseau, the French Resistance woman" adding that "where you join with the French Resistance is a really nice moment". And, again, she appears to be a real person: Jeannie Rousseau (opens in new tab), an "Allied intelligence agent in occupied France during World War 2."
In real life she worked to disrupt the German's V1 and V2 rocket programs and, with that in mind, I'll just bring up this quote from Condrey he made during my presentation:
"We actually found phenomenal amounts of material that provided that high-action, blockbuster sort of experience that Call of Duty is known for, and it was really amazing because we didn’t have to invent it. These were things that happened. I mean, the V2 Rocket – the first entry in humans into space travel happened in World War 2; we stood on the site of the V2 Rocket and felt 'Wow!'”
That doesn't actually prove anything but could suggest the new game might touch on that area of the war.