Why Sweden was not in World War 2?

Answer 1

There was nothing to gain for Sweden by joining. As they were not allied to either of the warring factions. Also its neutrality secured itself a position as one of the richest countries of the world due to much of the resources and machinery needed to rebuilt the bombed states came from Sweden.

Answer 2

Sweden decided that they were just going to be neutral during the war. Sweden has actually held a neutral stance since the end of 1815. Of the twenty countries that at the beginning of the war said they were neutral, only seven remained neutral through out the whole war. Sweden did allow German troops to travel through Sweden on leave and to use their railways while Germany was just starting to fight the Russians. Sweden also became a huge safe haven for Jews from Denmark and Norway.