Igirisu means England the way England means Britain. ^^;; People may use it as a shorthand for England, or because they don't know that England =/= Britain, but it officially refers to the UK. (It would be more of a confusion if he was called Eikoku, since in my experience that word is often used to mean England in popular language, not officially, though.)
I don't recall any official merchandise that calls him England, but there are several mistakes in other languages in volume 3: he's called "United Kingdom" in English, Japanese, Chinese, Polish, Lithuanian and Hungarian, but "England" in other languages. (Btw, America is "America" in every language except for Chinese, obviously, and Spanish in which it's United States... o_o ) All of the "England" words mean, of course, England, but can refer colloquially (and incorrectly) to the UK. So basically, from what I see, this is a mistake that Himaruya keeps making.
As for football, there's no British national football team, so obviously, in such occasions he just represents England and his brothers probably represent their own national teams. (In football the English team is referred to as Ingurando (England) not Igirisu, but even in those strips Himaruya called him Igirisu. I suppose he just calls him that for simplicity's sake, even in situations when he is just England.)
no subject
I don't recall any official merchandise that calls him England, but there are several mistakes in other languages in volume 3: he's called "United Kingdom" in English, Japanese, Chinese, Polish, Lithuanian and Hungarian, but "England" in other languages. (Btw, America is "America" in every language except for Chinese, obviously, and Spanish in which it's United States... o_o ) All of the "England" words mean, of course, England, but can refer colloquially (and incorrectly) to the UK. So basically, from what I see, this is a mistake that Himaruya keeps making.
As for football, there's no British national football team, so obviously, in such occasions he just represents England and his brothers probably represent their own national teams. (In football the English team is referred to as Ingurando (England) not Igirisu, but even in those strips Himaruya called him Igirisu. I suppose he just calls him that for simplicity's sake, even in situations when he is just England.)