>>98893064Finland has a Swedish-speaking minority the same way Canada has a French-speaking minority. People's nationalities aren't dependent on their mother tongue, and if you've written something in your mother tongue it's easier to offer that to publishing houses operating in that language instead of having to translate it.
Moomin was not first published in Sweden, though, that's a lie. Söderström & Co which published the first book was a Finnish publishing house, focusing on Swedish-language stuff catering to the Swedish-speaking minority.
So a similar example would be, for example, a comic made in Canada, but made by a French-speaking Canadian, in French, and published in Canada through a Canadian publisher focusing on French-language stuff, if such would exist.