Complex sentence: Asser describes her as behaving "like a tyrant" and ultimately accidentally poisoning Beorhtric in an attempt to murder someone else; he finishes by describing her death as a beggar in Pavia.
Split into simpler sentences: Asser describes her as behaving "like a tyrant" and ultimately accidentally poisoning Beorhtric in an attempt to murder someone else. He finishes by describing her death as a beggar in Pavia.