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>Was it a patriotism thing, to ignore the world's most popular sport, and make their own one where America will always be no. 1?

In America they were playing something like rugby football and eventually dropped the rugby part at roughly the same time England was playing association football and dropped the association part. It was hardly the most popular worldwide sport at the time.

For example in European-ish countries it's called Calcio (to kick) in Italy, Nogomet (leg) in Boznia/Croatia, mappa (ball) in Cyprus, labdarugas officially (ball-kicking) in Hungary.

There's another 8 or so countries where it's called another form of kick/ball/leg/something etc.

Finally it's called soccer in about 15 countries, of which the USA is only 1, where almost none of them have another variant of football.

Fun fact: the term originated in England.

From https://en.wikipedia.org/wiki/Football

"Football is a family of team sports that involve, to varying degrees, kicking a ball to score a goal. Unqualified, the word football normally means the form of football that is the most popular where the word is used."

Why call it soccer? Maybe it's because the English, who invented it, called it that in 1895.

"The term soccer comes from Oxford "-er" slang, which was prevalent at the University of Oxford in England from about 1875, and is thought to have been borrowed from the slang of Rugby School. The slang also gave rise to rugger for rugby football, fiver and tenner for a five-pound and ten-pound note, and the now-archaic footer for association football.[12] The word soccer (which arrived at its final form in 1895) was first recorded in 1889 in the earlier form of socca.[13]"

So, you see, when the Aussies call their thing "football" it's an interesting cultural quirk but when Americans do the same it's because they are big dumb. And how ignorant and culturally domineering of them to call a sport by the name that the inventors of that sport coined for it. Man, these Americans!