Question: What did the Anglo-Saxons fail to prevent during the battle which inspired the J.R.R. Tolkien work The Homecoming of Beorhtnoth Beorhthelm's Son?
{'answer': 'Viking invasion', 'supporting_facts': [["The Homecoming of Beorhtnoth Beorhthelm's Son", 0], ["The Homecoming of Beorhtnoth Beorhthelm's Son", 1], ['The Battle of Maldon', 0]]}