It is generally assumed that Eyjafjörður was first settled in 890 by Helgi the Lean and his wife Þórunn Hyrna. Helgi was born in Ireland of a Swedish father and Irish mother. Þórunn Hyrna was born in Norway. Most people in Eyjafjörður, and indeed all Iceland can now trace their linage to these two.
The main attractions of Eyjafjörður at that time were fertile lowland valleys and the calm waters in the fjord, ideally suited for sheltering trade vessels. Commerce with agricultural products were important for the local economy from early on but the ocean gave valuable resources as well. For centuries, marine resources were harvested by small rowing vessels mostly for subsistence.
The most important fish in Iceland has always been the cod and fishermen in Eyjafjörður have fished cod since settlement. But the problem was that the cod in northern Iceland was available in greatest quantities in the summer. But in the summer all hands were needed on the farms gathering hay and tending the animals. The great cod fisheries in Iceland were therefore mostly along the southern and western coasts where cod was available in great quantities in late winter and spring. Farmers and farm workers from northern Iceland traversed the highlands each winter to participate in the spring cod fisheries with other people from other parts of Iceland.
This pattern began to change in the 19th century when the farmers in Eyjafjörður began to use large, decked sailing boats that allowed them to venture farther from the coast. The first commercial fisheries in Eyjafjörður did not specifically target cod, but Greenland shark for its oil rich liver. In the last decades of the 19th century the herring fishery began and northern Icelandic fishermen became the leaders in the herring fishing Greatly simplified, the social development of northern Iceland was therefore affected by Greenland shark and herring while in southern Iceland it was the cod that shaped the society.
Greenland shark fisheries gradually declined in the beginning of the 20th century due to competition from mineral oil. Then the herring took over as the most important commercial fishery in the north. Since the mid-20th century, and especially after the collapse of North Atlantic herring stocks in 1967, trawlers have become more and more important for fishermen in Eyjafjörður. Nowadays, about 20% of all Icelandic trawlers are based in Eyjafjörður and they are fishing all around Iceland, even outside Icelandic waters.
In addition to the commercial fisheries, the people of northern Iceland use the ocean as a basis for subsistance and sport fishing, farming of fish and shellfish, and recreational activities such as whale watching, scube diving, sailing, and kayaking. In recent years Eyjafjörður has become a popular stop for large cruise ships from Europe during the summer.