The Norwegian Vikings traveled to Ireland in 800. The influence of the Norwegians in Scotland and Ireland lasted throughout the Middle Ages. They founded the city of Dublin in about 840. It was the center of Viking power in Ireland for many years. Most of the Irish people are descended from peoples who began settling in Ireland about 2,400 years ago. These peoples included Celts, Vikings, Normans and Englishmen. Each group influenced Irish civilization and helped shape the character of the Irish people.