The Icelandic People won't be too happy about this.

The Russians succeed in occupying Denmark right at the end of World War II. They get troops into Denmark before the Allies can.
This results in two Danish governments being formed. A People's Republic in Copenhagen and a Constitutional Monarchy in Rejkavik. Obviously Iceland does not gain it's independence from Denmark. In fact half the Danish population flees to Sweden from whence they are transported, over 1 million to Iceland and 250,000 to develop Greenland, completely submerging the indigenous Innuit population.