In 1016, the same year that Canute invaded England and claimed the throne for himself, Harald Hardrada was born in Norway. (Actually, he didn’t acquire the name Hardrada (“Hard Ruler”) until he became king. Until them, we was plain old Harald Sigurdsson.) Harald grew up a normal Norwegian child, learning to fight and plunder, along with his half-brother, Olaf, who became King Olaf II. They fought side-by-side in many battles until Olaf was killed, at the Battle of Stiklestad in 1030. This battle has become one of the most famous in the history of Norway. It took place during Olaf’s campaign to spread Christianity through his country. A powerful group of men opposed Olaf’s efforts and met him on the field of battle. When they emerged victorious, Harald went into hiding, in Kiev.
He came back a full 15 years later, to become king. He then went about solidifying the kingdom, following in the footsteps of his half-brother, who had by then become St. Olaf.
Another reason that Harald had gone into hiding was that one of his and Olaf’s other enemies, Canute, had elevated his fortunes considerably by adding King of England to his title of King of Denmark. Canute died in 1035, but his successors kept a firm hand on England and Denmark. The one successor that gave Harald the most trouble was Sven. The two men battered each other for almost 20 years, finally patching things up in 1064.
His home front in order, Harald found it palatable to expand to the west. As was the fashion after the death of Edward the Confessor, Harald put in a claim for the throne of England, based on a promise that his father had allegedly been given by Hardicanute, who ruled England for a handful of months in 1042.
The English were having no more of Norse rulers, however, and cast their lot with Harold Godwinson, who up until that time had been the Earl of Wessex. Well, a good many of them did. One who didn’t quite like the way that Harold was handling the whole matter was Tostig, his own brother. Tostig was, by this time, an accomplished military commander and politician. He had a few years before been named Earl of Northumbria and rather liked the prestige and power that that title gave him. But he rather wanted more as well. Like other leaders of his time, he wanted the big prize. Choosing a rather odd way of going about it, he tightened the controls on the people of Northumbria so much that they revolted and thrust him from power. He fled to Flanders and waited in scheming sullenness for the opportunity to regain his title and also harass his brother, whom he undoubtedly blamed for his current misfortunes.
Tostig found a willing ally in the newly enthroned King Harald, who by this time had earned his surname of Hard Ruler by sporting an iron fist that would have made Canute proud. Together, they determined that they would invade England in early September.