Cognomen Karl-Oskar (Karl-Oskar 
) , in all the world, is an extremely rare surname. Predominantly, Karl-Oskar is the forename as well as the last name. Parts of the name also exists independently as a first name Karl, and a first name Oskar.
Elf, Pedersen, Rottmann, Davidsson, Grimstad, Lidström, Eriksson, Hallberg, Hedström, Hokkanen, Andersson, Bengtsson, Brännström, Johansson, Nicolaisen, Gunnarsson, Karlsson, Blomberg, Svensson, Sandberg, Luts, Kalow, Rikås, Gladh, Olsen, Sævik, Kivioja, Tjernström, Djärf, Hildor, Olming, Streith, Ankarberg, Brander, Lundell, Jönsson, Janzon, and Fredriksson