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Why do Americans call it soccer and the English call it football?

The United States is one of the few places where the game of kicking a ball into a net is called soccer—the rest of the English-speaking world calls it football, particularly in the United Kingdom. Ironically, we Americans started calling it soccer (not football) because of the British.
Football/soccer in England is governed by a complicated hierarchy of different levels of teams, or “associations.” About 200 years ago then, the sport became most commonly known in the U.K. as association football. It had been known as football, but the rise in popularity of rugby—or rugby football as it was known—prompted the need for distinction. Over time, “soccer” took hold as the preferred term, with “socc” coming from the “association” part of “association football.” (And for its part, rugby similarly, albeit briefly, was called “rugger.”)
Another game gained in popularity in both the U.K. and the U.S. in the 1800s as well. Based on medieval games, they called it “gridiron” in the U.K., and “football” in the U.S.—hey, the name wasn’t taken, and early football involved a lot more kicking than it does today.
Soccer was still widely used in England well into the 20th century, often interchangeably with football. Around the late 1970s, when pro soccer enjoyed a brief spell of popularity in the U.S., linguists say that the British reacted by football completely replacing soccer in the British vernacular. “Soccer” was just too “American” of a word.
But in the last few decades, the sport that Americans call football has been gaining in worldwide popularity. That’s due in part to the minor league NFL Europe, which used to be called the World League of American Football. And that’s what countries who already have “football” then call football: American football.
(This is to say nothing of Australian rules football, which is closer to rugby than either sport called football, or Canadian football, which is a variation of American football.)