Uchtred or Uhtred, called the Bold (died 1016), was the ealdorman of all Northumbria from 1006 to 1016, when he was assassinated. He was the son of Waltheof I, ealdorman of Bamburgh, whose ancient family had ruled from the castle of Bamburgh on the Northumbrian coast.
In 995, according to Symeon of Durham, when the remains of St Cuthbert were transferred from Chester-le-Street to Durham, Uhtred went to Durham with his monks to clear the site of the new cathedral. The new cathedral was founded by Bishop Aldhun, and Uhtred married Aldhun's daughter, Ecgfrida, probably at about this time. From his marriage he received several estates that had belonged to the church.
In 1006 Malcolm II of Scotland invaded Northumbria and besieged the newly founded episcopal city of Durham. At that time the Danes were raiding southern England and King Ethelred was unable to send help to the Northumbrians. Ealdorman Waltheof was too old to fight and remained in his castle at Bamburgh. Ealdorman Ælfhelm of York also took no action. Uhtred, acting for his father, called together an army from Bernicia and Yorkshire and led it against the Scots. The result was a decisive victory for Uhtred. Local women washed the severed heads of the Scots, receiving a payment of a cow for each, and the heads were fixed on stakes to Durham's walls. Uhtred was rewarded by King Ethelred II with the ealdormanry of Bamburgh even though his father was still alive. In the meantime, Ethelred had Ealdorman Ælfhelm of York murdered, and he allowed Uhtred to succeed Ælfhelm as ealdorman of York, thus uniting northern and southern Northumbria under the house of Bamburgh. It seems likely that Ethelred did not trust the Scandinavian population of southern Northumbria and wanted an Anglo-Saxon in power there. 
After receiving these honours Uhtred dismissed his wife, Ecgfrida, and married Sige, daughter of Styr, son of Ulf. Styr was a rich citizen of York. It appears that Uhtred was trying to make political allies amongst the Danes in Deira. Through Sige, Uhtred had two children, Eadulf, later Eadulf III, and Gospatric. This Gospatric's grandson was the infamous Eadwulf Rus who murdered Bishop Walcher.
In 1013 King Sweyn Forkbeard of Denmark invaded England, sailing up the Humber and Trent to the town of Gainsborough. Uhtred submitted to him there, as did all of the Danes in the north. In the winter of 1013 Ethelred was forced into exile in Normandy. After London had finally submitted to him, Sweyn was accepted as king by Christmas 1013. However he only reigned for five weeks, for he died at, or near, Gainsborough on 2 February 1014. At Sweyn's death, Ethelred was able to return from exile and resume his reign. Uhtred, along with many others, transferred his allegiance back to Ethelred, on his return. Uhtred also married Ethelred's daughter Ælfgifu about this time.
In 1016 Uhtred campaigned with Ethelred's son Edmund Ironside in Cheshire and the surrounding shires. While Uhtred was away from his lands, Sweyn's son, Cnut, invaded Yorkshire. Cnut's forces were too strong for Uhtred to fight, and so Uhtred did homage to him as King of England. Uhtred was summoned to a meeting with Cnut, and on the way there, he and forty of his men were murdered by Thurbrand the Hold, with assistance from Uhtred's own servant, Wighill and with the connivance of Cnut. Uhtred was succeeded in Bernicia by his brother Eadwulf Cudel. Cnut made the Norwegian, Eric of Hlathir, ealdorman ("earl" in Scandinavian terms) in southern Northumbria. 
The killing of Uhtred by Thurbrand the Hold started a blood feud that lasted for many years. Uhtred's son Ealdred subsequently avenged his father by killing Thurbrand, but Ealdred in turn was killed by Thurbrand's son, Carl. Ealdred's vengeance had to wait until the 1070s, when Waltheof, Ealdred's grandson had his soldiers kill most of Carl's sons and grandsons. This is an example of the notorious Northumbrian blood feuds that were common at this time. 
Uhtred's dynasty continued to reign in Bernicia through Ealdred, Earl of Bamburgh (killed 1038) his son from his marriage to Ecgfrida, and Eadulf (killed 1041) his son from his marriage to Sige, and briefly Eadulf's son Osulf held the earldom of northern Northumbria 1067 until he too was killed. Eadulf's brother Gospatric began the Swinton Family dynasty, his son Eadulf Rus famously murdering William Walcher, Bishop of Durham which led to William the Conqueror sending an army northwards to harry the region again. Uhtred's marriage to Ælfgifu produced a daughter, Ealdgyth, who married Maldred, brother of Duncan I of Scotland and who gave birth to a son, Gospatric, who was Earl of Northumbria from 1068 to 1072. 
Adrian Mourby's two Radio Plays, The Corsaint (c.1986) and its sequel, The King of the North Rides his Horse through the Sky (1992) provide convincing dramatic realisations of the story of the siege of Durham and the severed heads on poles as told about the historical Uhtred. They were broadcast by BBC Radio 3.