So the question becomes, what unpleasant historical factoids about your country have you found that history class / the bulk of mass media like to gloss over? Here, I'll start.
- Sterilization of undesirables. Sanctioned by law, the idea of pruning unwanted traits from the Swedish population was formalized in the 1930s. The notion was to prevent the proliferation of those who were afflicted with heriditary defects - mental illness, apathy, asociality, and promiscuity. This law was practiced until formally disbanded by Olof Palme in 1976 (an event rather more embarrassingly famous than the actual existence of the law). An estimated 90% of the forcibly sterilized were women.
- The assimilation of the Sami. The Sami, the indigenous population of northern Scandinavia, were like many other aboriginal people considered in the way of proper god-fearing Abrahamites. The usual circus of encroaching on land, dividing families and prohibition of language ensued, so that Sami children would grow up outside the dangerous influence of heathen elements. Since a large part of the Sami culture involve the herding of reindeer, they were particularly vulnerable to land grabs and poaching.
The conflicts have now abated somewhat - to my understanding there has been no actively enforced ethnic cleansing in a hundred years or so - but even today, the conflicts between Norrlanders and Lapps remain. - Sweden's little flirt with Nazi Germany. It's not a secret that a lot of Swedes, neutrality nonwithstanding, harbored deep sympathies for Nazi Germany. Like the Swedes, the German race were a cultured people, an oasis of civilization in a sea of savagery. Or something. The notion that Swedish people were inherently of a superior breed was unsurprisingly an attractive one, and one on which Germans and Swedes were in touching agreement. Of course, the end of the war revealed that it hadn't been like that at all. Suddenly, everyone hated the Nazis, had in fact hated them all along. Nazi paraphernalia was quietly swept under the rug, and with it the dream of Swedish cultural dominion over the lesser races. C'est la vie.
- On a related note, Sweden pioneered a lot of things. Like eugenics. The State Institute for Race Biology was the first of its kind in the world. Sanctioned by all governmental parties, it was founded in 1922, and addressed what was then known as the degeneration issue, a societal topic of intense interest during that time. The perceived danger of a "poisoning of society's body" and that the "material of the populace" would be "diluted" was great, and a solution had to be found in science. And this was done until 1956, when the government saw fit to disband the Institute, to the great dismay of all who would chart the hereditary basis of alcoholism, willfulness, criminality and insanity.