Abstract
The psychological term "sibling rivalry" may be employed to analyze geo-cultural similarities between the twin pair of rival powers Spain- Portugal, and Sweden-Denmark. This national competitiveness between closely related peoples with their alternating superiority and inferiority complexes also explains why the two minor powers Denmark and Portugal embarked upon a period of cooperation (1425-1476) which may have led to the "(Re)discovery of America" and for the persistent refusal of scholars and the general public in both countries to acknowledge the commonly held view that "Columbus discovered America."