The Great Men and Historical Characters are not, by any means, the only people in history. They just hog the limelight. The overwhelming majority of the world's population have names and faces, but they're still nameless and faceless. On the world stage, they're extras; in the libretto of history, they're the ticket attendants, cameo roles and stage crew. If you mixed them in with plausible fictional characters, even historians probably couldn't tell the difference.
They are the OTL Unknown, and you'll probably wind up drawing from a lot of them to fill out your cast.
Were they real? Probably not. Does it matter? Absolutely not. Until the Point of Divergence, their actions weren't enough to change the course of history. All that matters is that they be alive when history diverges.