Germanic speakers referred to Britons as Welsh. This term eventually came to be applied exclusively to the inhabitants of what is now Wales, but it also survives in names such as Wallace, and in the second syllable of Cornwall. Cymry, a name the Britons used to describe themselves, is similarly restricted in modern Welsh to people from Wales, but also survives in English in the place name of Cumbria. The Britons living in the areas now known as Wales and Cornwall were not assimilated by the Germanic tribes, a fact reflected in the survival of Celtic languages in these areas into modern times. At the time of the Germanic invasion of Southern Britain, many Britons emigrated to the area now known as Brittany, where Breton, a Celtic language closely related to Welsh and Cornish and descended from the language of the emigrants, is still spoken. In the 9th century, a series of Danish assaults on northern English kingdoms led to them coming under Danish control (an area known as the Danelaw). In the 10th century, however, all the English kingdoms were unified under one ruler as the kingdom of England. In 1066, England was conquered by the Normans, who introduced a French ruling Úlite that was eventually assimilated. Wales came under Anglo-Norman control in 1282, and was officially annexed to England in the 16th century.
On 20 October 1604 King James (who had succeeded separately to the two thrones of England and Scotland) proclaimed himself as "King of Great Brittaine, France and Ireland", a title that continued to be used by many of his successors. However, England and Scotland each remained legally in existence as separate countries with their own parliaments until 1707, when an Act of Union joined both parliaments. That act used two different terms to describe the new all-island state, a "United Kingdom" and the "Kingdom of Great Britain". However, the former term is regarded by many as having been a description of the union rather than its formal name at that stage. Most reference books therefore, describe the all-island kingdom that existed between 1707 and 1800 as the "Kingdom of Great Britain".