Arsenal fans? Thousands, possibly tens of thousands. The Arsenal Copenhagen Facebook page has 2k members, Arsenal Denmark facebook page 18k. And nobody under 30 even uses Facebook. There were at least 5 dedicated Arsenal pubs for the final game yesterday (arranged with Arsenal Copenhagen), they were all absolutely rammed.
English football has always been huge across Scandinavia. In Denmark they used to show English league games on free to air national channels during their winter break. It continued all the way up until the turn of the millennia. I've met plenty of e.g. 60ish guys who are Leeds fans because they watched them when they were growing up in the 70s. I know Danes and other Scandis who have handed their club allegiance down through generations - in fact I found out my eldest had gone out celebrating with his Arsenal mate and his dad, who turned out to be a guy I used to watch matches with 20 years ago. And now the Premier League is eating all football everywhere it's not got any smaller here in Denmark. But even thirty years ago, all kids interested in football would have an English club (not all would stick with it mind, kids are kids) There are a generation in their late twenties to thirties that grew up with Henry and Bergkamp and Pires and Vieira, but there are also loads that are a lot younger that I'm not sure how they found the club