Harald was a formidable and ruthless warrior. Half-brother to King Ólafr Haraldsson, later called Saint Olaf, he was 15 when he fought among Olaf’s army in 1030 at the battle at Stiklarstað, north of Niðarós, and in the disastrous aftermath of Ólaf’s death fled to Kievan Rus’. According to Snorri Sturlason’s Heimskringla Harald first served in the army of the Kievan Grand Prince Yaroslav before traveling to Constantinople to join the fabled Varangian Guard, accumulating great wealth and fame as a warrior in the process. When he returned to Norway in 1043 his money and reputation gave him considerable advantage challenging his young nephew Magnús Ólafsson, called the good, for the kingdom. By 1046 Magnús had offered to resolve the conflict by sharing Norway with Harald as co-king. In 1047, following Magnús’s sudden and somewhat mysterious death, Harald became sole king of Norway.
I have never heard it claimed that Harald was a good man, or even a good ruler. Much of Snorri’s description of Harald’s reign is a recitation of terror attacks on various communities in Norway, feuds, murders of prominent farmers and local chieftains, and wars with the Danes and Swedes, fighting always under his famous raven banner “Landwaster”. He was known to be generous to his friends, but also covetous, quick tempered, proud, and vain. He was merciless and unforgiving to those he thought of as enemies or who had offended him in some way. In other words, he was in every way the perfect image of a Viking chieftain and his was a fairly typical reign of the Viking Age in Scandinavia, if perhaps somewhat more vicious than some.
Harald considered himself heir to the domain of the Danish king Knut Sveinsson, called the Great, who from 1016 until his death in 1035 ruled an empire that in the end included Denmark, England, and Norway. Harald’s claim on Knut’s lands was as heir of his nephew Magnús. In 1040 Magnús, as King of Norway, and Hardaknut, Knut’s son and King of Denmark, had ended their long wars over control of Norway by agreeing that the first of them to die would be succeeded by the survivor. When Hardaknut died in 1042 Magnús became heir to Knut’s empire, and thus when Magnús died in 1047 Harald inherited the claim. For practical reasons, Magnús had taken control only of Norway and Denmark. At the time of his death, Hardaknut was also king of England, but he was succeeded there by his half-brother Edward, called the Confessor. Magnús was involved in wars with Knut’s nephew, Sweyn Estridsson, for control of Denmark and thus was in no position at that time to advance his claim in England, and after Magnús’s death Harald was similarly involved and similarly unwilling to try to remove Edward from his throne.
In January 1066 Edward died childless and his brother-in-law, Harold Godwinson, claimed the throne. Tostig, a younger brother of the English Harold, may have believed himself to have as good a claim to the kingdom, or perhaps thought himself a better man, but he knew that he lacked the resources to oppose his brother. He fled to Norway and offered England to Harald, guaranteeing that the majority of the English nobles would support the Norwegian against his brother. The offer suited Harald’s ambitions — Snorri says that Harald was “inordinately covetous of power and of valuable possessions of all kinds” — and in September a Norwegian fleet of 300 longships and some 15,000 men appeared on the English coast. The Norwegians quickly defeated the local English forces, and Harald, apparently confident that Godwinson had no choice but to surrender the country to him, began collecting tribute from the inhabitants. Harald took half his forces, leaving the other half with the ships. Believing that there was little danger the Norwegians traveled away from their ships with only light armor and light weapons.
Harold Godwinson, however, had no intention of giving up his kingdom. He had been waiting in the south, anticipating an invasion from Normandy, but on learning of the Norwegian forces he managed to march his army from London to York in only four days. On 25 September Godwinson’s heavily armed English army surprised Harald’s lightly armed forces at the bridge over the River Derwent. Before the battle Harold Godwinson is said to have offered his brother Tostig a third of England if he would not fight; to Harald Sigurðarson he offered “seven feet of English soil, or so much more as he is taller than other men.” Tostig chose to remain loyal to his Norwegian ally.
The battle is said to have lasted all day. Snorri says that in the thick of the fighting Harald, running out in front of the battle line, was struck in the throat by an arrow. After Harald’s death fighting paused, and Harold Godwinson offered peace to Tostig and the Norwegians. They refused his offer; the battle resumed, and the English army overwhelmed the remaining Norwegians, despite the arrival of the half of Harald’s army that had been left with the ships. So many died, the Anglo-Saxon Chronicle says, that the survivors required only 24 ships for their return to Norway.
And thus, some say, upon the death of perhaps the greatest Viking chieftain, the Viking Age came to an end.