Do you mean the most recent migration?
Most recently, Europe has experienced a significant migration from Asia and Northern Africa, with some more specific migrations, such as Turkish Migration in Germany and Austria and I think Somalian migration in Sweden.
Some of the effects is the visibility of Islam in those countries, most visible through female headscarves. Another effect was the shift in food, with more and more Europeans accepting Kebab and Chinese noodles as a form of "fast food". Also, the societies have become less homogenous.