The original conquest of Poland by Germany was greeted mostly as a repeat of ww1 by the Swedish citizens and the Swedish state. The grand powers were at war and neutral countries in between them (such as Luxembourg and Belgium) were in danger, but other neutral countries should not be. Up to the invasion of Denmark and Norway, a lot of Swedes had sympathy for the German cause due to long-standing diplomatic, economical and academic ties.

The invasion of Denmark and Norway sent a deep shock through Swedish society. Danes and Norwegians spoke almost the same language (that are mutually intelligeble) and were considered brethren people. The brutal conquest of Norway and Denmark soured the Swedish opinion of Germany, and any German diplomatic or economical advances were met with lukewarm enthusiasm at best after that.

Swedes did not run, but rather become more resolved to fight should they be invaded, instituted a lot of protection against "coup-like" attacks and introduced the "porcupine doctrine" - friendly, but painful to attack.