Operation Weserübung's effects on Sweden became strategically encircled by the German-Soviet pact. Since the Baltic states; Estonia, Latvia, and Lithuania; had been forced to accept "limited" Soviet forces on their soil, in the autumn of 1939, they were de facto more or less in a state of occupation. For Sweden and Finland, this meant that the only possible trade route to nations other than Germany and the Soviet Union, was through Petsamo harbour, in the far north of Finland. This seriously hampered the supply situation in both these nations. It also meant that an invasion of Sweden could be launched from almost any direction. Sweden
Midsummer Sweden, Denmark, Norway, Finland, Estonia, Latvia and Lithuania – but is also very strongly observed in Poland, Russia, Belarus, Germany, Netherlands, Flanders, Ireland, parts of the United Kingdom (Cornwall especially), France, Italy, Malta, Portugal, Spain, Ukraine, other parts of Europe, and elsewhere – such as Canada, the United States, Puerto Rico, and also in the Southern Hemisphere (mostly in Brazil, Argentina and Australia). In Estonia, Latvia, Lithuania and Quebec (Canada), the traditional Midsummer day, June 24, is a public holiday. So it was formerly also in Sweden and Finland, but in these countries it was, in the 1950s, moved to