Napoleonic Zombies

We all know the story of Napoleon’s push to Moscow, he burned the city and was pushed back to France by the Coalition. But what if it had went differently? During Napoleon’s invasion of Russia, they had felt an eerie feeling about their fallen comrades, nevertheless Napoleon urged his troops to push on to Moscow. He and his army successfully scorched Moscow, but when the Russians drove them out something strange happened, the dead had crawled out of their graves. Napoleon witnessed his decayed soldiers feasting upon his army, so he and his remaining soldiers had made the smart decision and fled to Berezina where they presumably had fought to cross the bridge and return to France. The only places that hadn’t been affected by the undead plague had been Great Britain and other places similar to it like the Americas, as they had the Channel and Oceans between them