Last name Guðbjörg (Guðbjörg 
) , around the globe, is an extremely rare cognomen. Much more frequently, Guðbjörg is the forename as well as the last name.
Rós, Jóhannesdóttir, Jóhannsdóttir, Eiríksdóttir, Hjartardóttir, Friðriksdóttir, Ingólfsdóttir, Ágústsdóttir, Þorvaldsdóttir, Þorsteinsdóttir, Stefánsdóttir, Pétursdóttir, Ragnarsdóttir, Gunnarsdóttir, Guðmundsdóttir, Halldórsdóttir, Sigurðardóttir, Sigurgeirsdóttir, Kristjánsdóttir, Kristmundsdóttir, Guttormsdóttir, Ingimundardóttir, Jakobsdóttir, Gústafsdóttir, Gísladóttir, Gissurardóttir, Másdóttir, Lilja, Forup, Pálsdóttir, Gylfadóttir, Leifsdóttir, Jónsdóttir, Torfadóttir, Hauksdóttir, Helgadóttir, Valdimarsdóttir, Finnsdóttir, Sveinsdóttir, Andrésdóttir, Arnardóttir, Birgisdóttir, Guðjónsdóttir, Árnadóttir, Óskarsdóttir, Ólafsdóttir, Björnsdóttir, Bjarnadóttir, Magnúsdóttir, and Sveinbjörnsdóttir