In the period from 800 to 1050 A.D., the Nordic peoples made their dramatic entry into the European arena. Early writers called them Vikings, which means 'inlet-men', because they came from the deep inlets of Scandinavia.

The explosive expansion of the Vikings was the result of Scandi-navian overpopulation troubles, which skill in navigation made exportable. The Vikings had developed the long-boat, which by its shallow draught could sail far up rivers, and which by its sturdy construction could ride out the fiercest storms of the Atlantic ocean. They were raiding all the European coasts down to Spain and along the rivers into the heart of Europe.

The Danish vikings plundered Frankish cities and undertook campaigns as far as Portugal and Italy. They subjugated parts of England and for a short time established a North Sea empire.

The Swedish vikings undertook campaigns in E'Europe and along the rivers of Russia all the way to the Black Sea and Constantinople.

The Norwegian vikings occupied the Orkneys, the Shetlands and Ireland. They braved the northern seas until they arrived in Iceland and around AD 1000 they reached Greenland and discovered America.