Complex sentence: Hermann was the son of the Eastphalian count Billung von Stubenskorn (c.860-967) and Ermengarde of Nantes, he was the younger brother of the Saxon count Wichmann the Elder.
Split into simpler sentences: Hermann was the son of the Eastphalian count Billung von Stubenskorn (c.860-967) and Ermengarde of Nantes. He was the younger brother of the Saxon count Wichmann the Elder.