No horrid war conditions in the U.S. It seems to be true that the flu started in the the U.S. and spread to Europe through our soldiers. And apparently spread elsewhere from Europe.
They're saying it hit India hard and probably due to their drought. Maybe more so due to their population density.
Still lots of speculation here.
Actually, they’ve traced the beginnings of the flu to Alaska and the garrisoned U.S. troops there, who were subsequently transported across North America and to Europe, where they spread it throughout the former war zone.