Geschichte Mitteldeutschland 2.0 » Were the slavic people agressors?

Were the slavic tribes aggressors? Or did they inhabit empty land?

The Slavs basically took over half of europe in a matter of a century, and still holds the ground. Where did they come from? Some say that they are the Germanic cousins. Afterall they are the largest Indo-European group.


I didn't find the right solution from the internet.
References:
http://hist orum.com/european-history/127707-were-slavic-people-agressors.html
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