Question: At which battle, in the East Riding of Yorkshire, did King Harold defeat King Harald of Norway?

Context paragraphs:
High Sheriff of the East Riding of Yorkshire: The High Sheriff of the East Riding of Yorkshire is a current High Sheriff title which has existed since 1996.  For around 1,000 years the entire area of Yorkshire was covered by a single High Sheriff of Yorkshire.  After the Local Government Act 1972 the title was split to cover several newly created counties.  Most of the former area of the East Riding became part of the county of Humberside and under the High Sheriff of Humberside title.  Humberside was abolished in 1996 and a High Sheriff title was created for the newly reconstituted East Riding of Yorkshire.

1984–85 Yorkshire Cup: The 1984–85 Yorkshire Cup was the seventy-seventh occasion on which the Yorkshire Cup competition had been held.  This season there were no junior/amateur clubs taking part, no new entants and no "leavers" and so the total of entries remained the same at thirteen.  This in turn resulted in three byes in the first round.  In this year's final, Hull F.C. beat close neighbours and fierce rivals Hull Kingston Rovers by the score of 29-12.  The match was played at Boothferry Park, Kingston upon Hull.  The city was formally in the East Riding of Yorkshire, followed by Humberside and is now (back) in the ceremonial county of the East Riding of Yorkshire (albeit that the word "Riding" means "a third part" and there is now only one !) .  It was moved to this stadium from the provisionally reserved venue due to the interest showed by fans and after requests by both finalists, and the organisers were rewarded with a crowd of 25,237 and gate receipts more than doubled from last year's £33,572 to £68,639.  This is only the third meeting of these two clubs in the Yorkshire Cup final, on the two previous occasions Hull Kingston Rovers defeated Hull F.C., in 1920-21 by 2-0 and 1967 by 8-7; this time it was revenge and by a wider margin.  This is the third successive Yorkshire Cup final victory for Hull F.C. And the first of two successive Final appearances by Hull Kingston Rovers

East Riding of Yorkshire Archive Service: The East Riding of Yorkshire Archive Service holds the archives for the East Riding area.  The archives are held at Treasure House, Champney Road, Beverley, and run by East Riding of Yorkshire Council.

Ancestry of the Godwins: Very little is known for certain of the ancestry of the Godwins, the family of the last Anglo-Saxon King of England, Harold II.  When King Edward the Confessor died in January 1066 his closest relative was his great-nephew, Edgar the Ætheling, but he was young and lacked powerful supporters.  Harold was the head of the most powerful family in England and Edward's brother-in-law, and he became king.  In September 1066 Harold defeated and killed King Harald Hardrada of Norway at the Battle of Stamford Bridge, and Harold was himself defeated and killed the following month by William the Conqueror at the Battle of Hastings.

East Riding of Yorkshire: The East Riding of Yorkshire, or simply East Yorkshire, is a ceremonial county of England.  It is located in the region of Yorkshire and the Humber.  The East Riding of Yorkshire may also refer to a local government district with unitary authority status, which does not include the city of Kingston upon Hull, the largest settlement in the ceremonial county, which is a separate unitary authority.  The modern East Riding of Yorkshire (both ceremonial county and unitary authority), was formed in 1996 from the northern part of the non-metropolitan county of Humberside.

Gryting, King of Orkdal: Gryting was according to Heimskringla a king of Orkdal in the period leading up to Harald Fairhair's unification of Norway.  He was the first leader in Trøndelag to make a stand against King Harald's ravaging of the country.  At the battle of Orkdal Gryting's men were defeated and Gryting taken prisoner.  After this Gryting swore allegiance to king Harald.

The Beverley Treasure House: The Treasure House is a cultural centre operated by the East Riding of Yorkshire Council in the town of Beverley in the East Riding of Yorkshire, England.  The centre acts as the main hub for heritage and information services, and contains the East Riding Archives and Local Studies, the Beverley Library, a Museum and the Beverley Art Gallery.  The building also contains a coffee lounge and gift shop.  The top floor, known as 'The Tower', serves as an elevated sightseeing platform, showcasing 360 degree views of the Beverley Minster and the town of Beverley.

History of the East Riding of Yorkshire: The East Riding of Yorkshire is a local government district with unitary authority status, and is a ceremonial county of England.  It is named after the historic East Riding of Yorkshire which was one of three ridings alongside the North Riding and West Riding, which were constituent parts a Yorkshire ceremonial and administrative county until 1974.  From 1974 to 1996 the area of the modern East Riding of Yorkshire constituted the northern part of Humberside.

Olvir Hnufa: Olvir Hnufa or Ölvir hnúfa was a Norwegian hersir and skald of the late ninth and early tenth centuries, known from, among other sources, "Egil's Saga", "Skaldatal" and the "Prose Edda".  Olvir was the son of the viking Berle-Kari and brother-in-law of Kveldulf Bjalfason, who married Olvir's sister Salbjorg Karadottir; he was thus uncle to Skallagrim and Thorolf Kveldulfsson and great uncle to the famous poet Egil Skallagrimsson.  Olvir also had a brother named Eyvind Lambi.  Olvir was a prominent member of the court of King Harald Fairhair, who united Norway under his rule in the late ninth or early tenth century.  Among other famous skalds, he served as one of King Harald's court poets.  He also served as a warrior in Harald's retinue, and fought at the pivotal Battle of Hafrsfjord on the king's flagship.  He is best known for his involvement in the conflict between Harald and Olvir's kinsman Thorolf Kveldulfsson, which ended with the latter's death.  Only a few fragments of Olvir's poetry survive.

Battle of Stamford Bridge: The Battle of Stamford Bridge took place at the village of Stamford Bridge, East Riding of Yorkshire, in England on 25 September 1066, between an English army under King Harold Godwinson and an invading Norwegian force led by King Harald Hardrada and the English king's brother Tostig Godwinson.  After a bloody battle, both Hardrada and Tostig along with most of the Norwegians were killed.  Although Harold Godwinson repelled the Norwegian invaders, his army was defeated by the Normans at Hastings less than three weeks later.  The battle has traditionally been presented as symbolising the end of the Viking Age, although major Scandinavian campaigns in Britain and Ireland occurred in the following decades, such as those of King Sweyn Estrithson of Denmark in 1069–1070 and King Magnus Barefoot of Norway in 1098 and 1102–1103.

Supporting paragraphs: Ancestry of the Godwins Battle of Stamford Bridge
Answer: Battle of Stamford Bridge