Scandinavians were certainly not the only people of their era to raid and pillage their neighbors, but they did it with greater frequency and a brutal efficiency not seen in other cultures. What drove them go i viking? There are several competing theories, and no single reason probably fully explains it. A combination of several factors likely caused the Vikings' bloodthirsty behavior.
- Terrain - Scandinavians lived on islands or peninsulas with no room to expand. The land was usually poor for farming or too mountainous to live on, and the climate was very cold. So they looked elsewhere, not only for places to settle or conquer, but for places where they could simply take the resources they lacked at home.
- Population pressures - Scandinavian cultures existed for several hundred years before they developed their reputation as plunderers. What changed? Population. Advances in agricultural technology and the climate allowed them to grow more food and farm more land. The additional resources lead to a healthier population, longer life expectancy and an overall population increase. This population pressure manifested as squabbles between various clans and kingdoms within Scandinavia, but it also manifested as a drive to leave home, explore and conquer new lands.
- Tradition - Coastal raiding may have started out as a simple job. Some Scandinavian men made their living doing this dangerous work. But it grew into a tradition that fed on itself, until virtually every male Scandinavian was lining up to join the raids. Young men were expected to test themselves in this manner.
- Exile - Viking law frequently relied on exile as a penalty for convicted criminals. When you send convicted criminals off in a longboat by themselves to exile, there's a good chance some coastal pillaging and plundering might occur.
- Greed - The Vikings wanted things: coins, livestock, thralls, treasures, spices, works of art, raw materials. They probably didn't want these things any more than other cultures did, and they often acquired them through simple trade. But with their skill at sea and violent tendencies, they often found themselves in a position to take whatever they wanted.