So this is official from the Roal family of Norway that Oslo is named after a bulgarian Princess named Miroslava , or Oslava !!!!
Well I can understand Harald :-) The Bulgarian girls are one of the most beautiful in the World. And I don't say this because I am Bulgarian, but because this is true. Many foreigners who came here say the same.
Or as one Medieval Persian poet writer said in 13 century AD:
"The beauty of the maidens in Heaven exceed even the beauty of the Bulgarian woman"
These maidens (called "Huri") are those 70 virgin girls from the Islamic Heaven (in that time Persia was already under Islam) who will serve the fallen in battle Islamic warriors. So this quote means that only the virgin maidens in Heaven are more beautiful than the Bulgarian girls. :-)
I don't know when this Persian poet saw a BG girl, but obviously her beauty was famous even in distant Persia.
So I think that the Viking king Harald was a man of good taste ;-)