Question: Ivan Blakeley is starring in the drama series "Vikings" as the King of Northumbria, England in the middle of what?

Context paragraphs:
Edmund Ætheling: Edmund Ætheling ( ;  1015–17 – possibly 1046, certainly by 1054) was a member of the royal House of Wessex as the son of Edmund Ironside, who briefly ruled as King of England between April and November 1016.  He fought the Danish Vikings under Cnut the Great, but following the Danish victory at the Battle of Assandun in October, it was agreed that Ironside would rule Wessex, while Cnut took Mercia and probably Northumbria.  In November 1016, Ironside died and Cnut became King of all England.

Æthelflæd: Æthelflæd, Lady of the Mercians ( 870 - 12 June 918) ruled Mercia in the English Midlands from 911 until her death.  She was the eldest daughter of Alfred the Great, king of the Anglo-Saxon kingdom of Wessex, and his wife Ealhswith.  Æthelflæd was born around 870 at the height of the Viking invasions of England.  By 878 most of England was under Danish Viking rule, East Anglia and Northumbria having been conquered and Mercia partitioned between the English and the Vikings, but in that year Alfred won a crucial victory at the Battle of Edington.  Soon afterwards the English-controlled western half of Mercia came under the rule of Æthelred, Lord of the Mercians, who accepted Alfred's overlordship.  Alfred adopted the title King of the English, claiming to rule all English people not living in areas under Viking control.  In the mid-880s, Alfred sealed the strategic alliance between the surviving English kingdoms by marrying Æthelflæd to Æthelred.

Ælla of Northumbria: Ælla (or Ælle) (fl.  866; d. 21 March 867) was King of Northumbria, England in the middle of the 9th century.  Sources on Northumbrian history in this period are limited, ancestry is not known and the dating of the beginning of Ælla's reign is questionable.

Somewhere in England (film): Somewhere in England is a 1940 British comedy film directed by John E. Blakeley and starring Frank Randle, Harry Korris and Winki Turner.  It follows the adventures of an anti-authoritarian private stationed in a military camp in the North of England during the Second World War.  It was the first in the "Somewhere" film series, followed by its sequel "Somewhere in Camp" in 1942.

Mercian dialect: Mercian was a dialect spoken in the Anglo-Saxon kingdom of Mercia (roughly speaking the Midlands of England, an area in which four kingdoms had been united under one monarchy).  Together with Northumbrian, it was one of the two Anglian dialects.  The other two dialects of Old English were Kentish and West Saxon.  Each of those dialects was associated with an independent kingdom on the island.  Of these, all of Northumbria and most of Mercia were overrun by the Vikings during the 9th century.  Part of Mercia and all of Kent were successfully defended but were then integrated into Wessex.  Because of the centralisation of power and the Viking invasions, there is little or no written evidence for the development of non-Wessex dialects after Alfred's unification, until the Middle English period.

Ivan Kaye: Ivan Blakeley Kaye (born 1 July 1961 in Northampton, Northamptonshire) is an English actor.  He previously played Dr. Johnathon Leroy in a recurring role in "EastEnders", and he played Bryan in "The Green Green Grass".  He also played the Duke of Milan in all three Seasons of "The Borgias", and is now starring as King Aelle, in History channel's historical drama series "Vikings".

Ragnall ua Ímair: Ragnall ua Ímair (Old Norse: "Rögnvaldr" , died 921) or Rægnald was a Viking leader who ruled Northumbria and the Isle of Man in the early 10th century.  He was a grandson of Ímar and a member of the Uí Ímair.  Ragnall was most probably among those Vikings expelled from Dublin in 902, whereafter he may have ruled territory in southern Scotland or the Isle of Man.  In 917, he and his kinsman Sitric Cáech sailed separate fleets to Ireland where they won several battles against local kings.  Sitric successfully recaptured Dublin and established himself as king, while Ragnall returned to England.  He fought against Constantín mac Áeda, King of Scotland, in the Battle of Corbridge in 918, and although the battle was not decisive it did allow Ragnall to establish himself as king at York.

Buena Familia: Buena Familia (lit.  Good Family) is a 2015 Philippine family drama series directed by Gil C. Tejada, starring Kylie Padilla, Martin del Rosario, Julie Anne San Jose, Jake Vargas and Julian Trono.  The drama series premiered on GMA Network and worldwide via GMA Pinoy TV on July 28, 2015, replacing the top-rating drama series "Yagit" on the network's Afternoon Prime block.  It was replaced by Hanggang Makita Kang Muli.  The drama series also features the return of the love team of Bobby Andrews and Angelu de Leon in Philippine television.

Sitric Cáech: Sitric Cáech, also known as Sitric Gále, (Old Norse: "Sigtryggr" , died 927) was a Viking leader who ruled Dublin and then Viking Northumbria in the early 10th century.  He was a grandson of Ímar and a member of the Uí Ímair.  Sitric was most probably among those Vikings expelled from Dublin in 902, whereafter he may have ruled territory in the eastern Danelaw in England.  In 917, he and his kinsman Ragnall ua Ímair sailed separate fleets to Ireland where they won several battles against local kings.  Sitric successfully recaptured Dublin and established himself as king, while Ragnall returned to England to become King of Northumbria.  In 919, Sitric won a victory at the Battle of Islandbridge over a coalition of local Irish kings who aimed to expel the Uí Ímair from Ireland.  Six Irish kings were killed in the battle, including Niall Glúndub, overking of the Northern Uí Néill and High King of Ireland.

Eadwulf Cudel: Eadwulf Cudel or Cutel (meaning cuttlefish) was Earl of Bernicia (or Bamburgh) in the early eleventh century.  Following the destruction of the kingdom of Northumbria by the Vikings in 867, they established the Kingdom of York in southern Northumbria, but English rulers held on in the north, the former kingdom of Bernicia, from their base at Bamburgh.  They were variously described as earls or ealdormen or high-reeves, and their independence from the kings of England and Scotland is uncertain.  Uhtred the Bold and Eadwulf Cudel were sons of Waltheof, earl of Bamburgh, who died in 1006.  He was succeeded by Uhtred, who was appointed by Æthelred the Unready as earl of the whole of Northumbria.  Uhtred was murdered in 1016, and king Cnut then appointed Erik, son of Hakon, earl at York, while Eadwulf succeeded at Bamburgh.

Supporting paragraphs: Ivan Kaye Ælla of Northumbria
Answer: the 9th century