The Battle of Stamford Bridge is a pivotal, but little recognized event in English history, its importance hidden by The Battle of Hastings which occurred a mere three weeks later.

The English king, Edward the Confessor had died and a dispute ensued over who was the rightful heir. Harold Godwinsson and Duke William of Normandy both wanted the throne. Godwinsson seized the throne and the Duke of Normandy began raising an army building an invasion fleet to cross the English Channel. The expected invasion didn't appear although anticipated throughout the summer of 1066. King Harold moved the English fleet to the Isle of Wight where it was hit by a storm on the way and crippled. King Harold also stepped down the watch on the English Channel and disbanded the English militia.

In the meantime, the Norwegian king, Harald Sigurdsson with the support of Earl Tostig (King Harold's brother) and Scottish sympathizers, invaded England from the north. The Viking invasion sailed up the River Humber and landed just south of York, a capital city. Battle ensued between the Viking invaders and a small English defending force. York fell to Harald, who left it almost immediately, marching east to Stamford Bridge. Stamford Bridge was located on a vital communication route over the River Derwent.

When he received news of the invasion, England's King Harold marched his army north and with surprising speed reached Stamford Bridge in five days. The English army caught the Viking invaders unaware. Early in the battle, the Vikings kept their battle order and the English were repulsed. The Viking army broke ranks and the English gained offensive. King Harold Sigurdsson was slain and Tostig took up the banner. The armies re-grouped and during a lull in the battle, King Harold offered his brother, Tostig, and the Vikings peace, which they refused. After a fierce battle, the Vikings lost. King Harold gave quarter and the Vikings, who had arrived in 300 ships, left in 24 ships.

The Battle of Stamford Bridge was the last Viking invasion in England. Most importantly though, this invasion by the Vikings forced the English army to march north. When Duke William of Normandy landed his invading army, they had time to move inland to good defensive positions before the English army returned from the north and The Battle of Hastings changed the course of English history.