You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "Ivar the Boneless had a brother who held what position in the mid-ninth-century?" whose answer is Viking chieftain.
Each document should contain about 30 words, and these documents should contain useful information.

Query: Ivar the Boneless brothers positions mid-ninth century
Useful Output:

Doc 1: HALFDAN I (brother of Ivar the Boneless):  A Mercian regnal list, extending from Penda in the mid-seventh century to Berhtwulf in the mid-ninth century.
Doc 2: When he says "this is one of the most deprived areas in the UK" at the beginning, I can literally see my house.
Doc 3: He was a famous warrior and one of the leaders of the 'Great Heathen Army' that landed in East Anglia in 865, and that went on to conquer the
Doc 4: Ivar the Boneless, or Ivar Ragnarsson, was the formidable Viking warlord of the Great Heathen Army in the late ninth century.
Doc 5: A 9th century Viking from Scandinavia named Ímar, (or Ívarr or Ivar) was the founder of this Uí Ímair dynasty. The identity of the original Ivar remains