By this time, what came to be called the Great Migration had occurred, and Slavic people from the east had begun to settle in the territory.
ते नाव होते ब्रेझालाउस्पुट्‌र्झ अर्थात “ब्रास्लाउचे महाल ”; एका मोठ्या सेनापतीच्या नावावरून हे नाव पडले असावे असे मानले जाते.