The Big Switch (The War That Came Early, Book Three) - Harry Turtledove

In 1941 Winston Churchill was Hitler's worst enemy. Then a Nazi secret agent changed everything.

What if Neville Chamberlain, instead of appeasing Hitler, had stood up to him in 1938? Enraged, Hitler reacts by lashing out at the West, promising his soldiers that they will reach Paris by the new year. Instead, three years pass, and with his genocidal apparatus not fully in place, Hitler barely survives a coup, while Jews cling to survival, and England and France wonder whether the war is still worthwhile. The stage is set for World War II to unfold far differently from the history we know-courtesy of Harry Turtledove, wizard of "what if?," in the continuation of his thrilling series: The War That Came Early.

Through the eyes of characters ranging from a brawling American serving with the Abraham Lincoln Brigade in Spain to a woman who has seen Hitler's evil face-to-face, The Big Switch rolls relentlessly forward into 1941. As the Germans and their Polish allies slam into the gut of the Soviet Union in the west, Japan pummels away in the east. Meanwhile, in the trenches of France, French and Czech forces are outmanned but not outfought by their Nazi enemy. Then the stalemate is shattered. In England Winston Churchill dies suddenly, leaving the gray men wondering who their real enemy is. And as the USSR makes peace with Japan, the empire of the Rising Sun looks westward-its war with America about to begin.