Technically, no. That’s why (I suppose) the author felt obliged to insert “(including Finland)” after “Scandinavia”. In the strictest sense Scandinavia includes Sweden and Norway, only. In a broader sense it includes Denmark and Iceland, as well. As far as I know, Finland has never been “Scandinavian”, especially considering that Finnish language and ethnicity are totally unrelated to those belonging to typical “Nordic” peoples.
- Apart from what I've pointed out above (concerning Finland having been a part of Sweden and since ages having shared many cultural traits of the “real” Scandinavian countries), Finland is, from a geographical point of view part of Fennoscandia.
Despite the fact that the Finnish language isn't a Nordic one, not even Indo-European in fact (about 5% are native Swedish speakers though), Finland is viewed as one of the Nordic Countries by the other Nordic countries.
Just like a lot of people who for generations have been plagued by Feudalism, Nazism and Communism the Finns are today taking part in creating something certain Germans (especially those who, for certain reasons, hate both Fascism and Communism) call Gross-Schweden!
A more suitable expression from a Swedish diplomatic stance might however be; The Greater Baltic Region.
Porsche Cayennes and Volvo XC90s to everyone!