Not sure on which thread I should post this but anyway ....
In the link below it states that, "The very first oval earth track, purposely built for motorcycle racing, in Scandinavia and most likely in Europe opened in Bagsvaerd, a suburb north of Copenhagen in 1920." I know that it’s generally accepted that the “first speedway meeting ever” was held at the West Maitland Showground in Australia in 1923. So, it’s possible that the style of racing at this Danish track was not speedway as we know it. However, according to Wikipedia, Morian Hansen stated riding in 1928 so presumably there were Danish riders before him.
http://speedwaylife.com/danish-tracks/history/