Europeans came up with the word "soccer" as a shortened form of "Association football" to distinguish it from the numerous other forms of football being played (rugby etc).
It was not Europeans. It was the British. And it was the upper class British. Specifically at the Oxford University.
The people in both continental Europe and Britain always called it football.
"Soccer" is technically a slur for lower class football.
Even the British call it football now, but the soccer slur still lives on in America and other colonies.
OK, so this may shock some, but my posh English school called football 'soccer'. Football was what most people would call rugby. Cricket was... Cricket.
😄 Thank you. Obviously not what I was referring to, but still a point.
In Japan the most common term is sakkā, that came into use from US influence after the war. Both futtobōru and football is in use, though.
Although the official English name of the Japan Football Association uses the term "football", the term sakkā (サッカー), derived from "soccer", is much more commonly used than futtobōru (フットボール). The JFA's Japanese name is Nippon Sakkā Kyōkai.
Before World War II the term in general use was shūkyū (蹴球, kick-ball), a Sino-Japanese term. With previously exclusive Japanese terms replaced by American influence after the war, sakkā became more commonplace. In recent years, many professional teams have named themselves F.C.s (football clubs), with examples being FC Tokyo and Kyoto Sanga FC.
soccer is an abbreviation of associated football. which apparently had rather upper class implications in the UK and as such the word never caught on with the hoi poloi