His parentage is confirmed in several places in the Anglo-Saxon Chronicle.
He was created Earl of the East Angles, Essex, Cambridgeshire and Huntingdonshire in 1044 by King Edward "the Confessor". King Edward granted him part of the earldom of his brother Svein, after the latter was outlawed following his seduction of the Abbess of Leominster. After joining his father's threatened armed rebellion against the king in 1051, he fled to Ireland with his brother Leofwine. He returned from Ireland the following year and joined forces with his father. Harold was appointed to succeed his father as Earl of Wessex in 1053, his own earldom of the East Angles passing to Ælfgar son of Leofric Earl of Mercia. He led the counter-offensive against Gruffydd ap Llywellyn Prince of Wales in 1063, in reprisal for Welsh raids. On a mission to France in , he was captured by Guy [de Ponthieu] Comte d'Abbeville and imprisoned at Beaurain. Guillaume II Duke of Normandy, Guy's suzerain, secured Harold's release, possibly in return for the latter's acknowledgement of Duke Guillaume as successor to the English throne, the event being recorded in the Bayeux tapestry. Guillaume of Jumièges records that “Edwardus Anglorum rex” had already sent “Rodbertum Cantuariorum archipræsulem” to Normandy to recognise Duke Guillaume as his heir, and that the king sent “Heraldum” as his representative to finalise the affair, that Harold landed at Ponthieu and was captured by “Widonis Abbatisvillæ comitis”, from whom Duke Guillaume rescued him and brought him back to Normandy where he swore allegiance to the duke, who retained “adolescentem Vulnotem fratrem eius” as hostage. According to Eadmer, the reason for Harold's visit to Normandy was to negotiate the release of his brother Wulfnoth and nephew Haakon, both of whom had been held hostage there since 1051. In spite of earlier promises to Duke Guillaume, on his deathbed King Edward "the Confessor" bequeathed the kingdom to Harold.
The choice was unopposed at court and Harold succeeded as HAROLD II King of England, crowned 6 Jan 1066. It is unclear whether there was a meeting, formal or informal, of a council to consider the matter, or whether members of such council took part in some form of election as it might be recognised today. There would probably have been little need for formality as the succession was presumably a foregone conclusion. Duke Guillaume branded Harold a perjurer and appealed to Pope Alexander II for support. After receiving a papal banner in response to this request, the duke gathered a sizable army during Summer 1066 ready for invasion. In response to the invasion by his brother Tostig and Harald III "Hardråde" King of Norway (who also claimed the throne of England), King Harold marched northwards and defeated the invaders at Stamford Bridge 25 Sep 1066. Harold returned south, but meanwhile Duke William's army had set sail from Saint-Valéry-sur-Somme 28 Sep. King Harold hastily reassembled his army to meet this second invasion at Hastings 14 Oct 1066, where he was killed.
The Chronique de Normandie, based on le Roman de Rou, records that King Harold II was killed at Hastings by "un chevalier…Robert fils Herveis". According to the Waltham Chronicle written some time after 1177, King Harold's body was identified on the battlefield by his mistress Eadgyth Swanneshals and taken to Waltham for burial. 1