I can’t speak about Iceland or Australia, but Norway has a huge number and percentage of immigrants, particularly from Somalia, Sri Lanka, Pakistan and more recently, Iraq and Afghanistan. It’s been a growing population (I believe it’s up to about 10% of the population), and a growing concern for native Norwegians, who have been a fairly homogenous group for centuries. They are now confronted with the same economic and cultural issues that other countries are dealing with.
Yes, Australia has a very high immigration rate as well - far higher than that of the US when compared to population (Australia takes in about 220,000 legal immigrants a year with a population of 22 million, the US with 14 times our population takes only about 5 times as many legal immigrants - including illegals, that rises to about 11 times).