England started to decline in late nineteenth century, but Germany started to rise after unification. This power vacuum at top allowed World War I to begin. England pulled it out by getting American aid. But Hitler tried it again. He was defeated again by America. World War II continued into the 1990’s. Germany switched sides in 1945. Germany became an ally and was rewarded with hegemony over Europe, its new kind of empire.
This is what Hitler wanted more or less minus Russia. Hitler was short-sighted about the political system, preferring dictatorship over democracy. But that was understandable coming out of World War I. Hitler and Hess wanted to make a deal with the Britain about powersharing. Hitler would control the Continent. Britain would control Africa, Asia, and the English-speaking world. That is sort of like what happened anyway if you consider America part of the English sphere of influence.