People in the middle ages believed that the world's population was divided into different peoples, gentes. Medieval authors often wrote of national characteristics determined by habits, temperament, lifestyle etc. Peoples were communities with a common descent, with blood ties the vehicle for a people's survival and expansion into the future.

This was reflected in the law. For example medieval Welsh legal codes distinguished between a full-blooded Welsh person (Cymrovamtad), who was automatically a gentleman, and foreigners. This was a fundamental principle of Welsh law. The 14th century English in Ireland outlawed intermarriage between English and Irish as undermining identity (they called it "degeneracy").

The French writer Claude Seyssel (1450-1520) claimed that "all nations and reasonable men prefer to be governed by men of their own country and nation who know their habits, laws and customs and share the same language and life-style as them-rather than by strangers".

This view seems to have been shared by ordinary people. A lowly English cleric called Henry Lambard in 1323 was taken to court on charges of theft and made his answer to the charges in English. As Latin and French were the legal languages of the time, he was asked to make his answer speaking in one of those languages. He refused, claiming that he was English and English-born and that he should speak in his mother tongue. He was subsequently punished.

As the historian R. R. Davies has claimed, "The medieval construction of the world, therefore, was one which defined it as a collection of peoples; what ever modern historians care to believe, contemporaries were not in doubt about the reality and solidity of such communities".

Sources: R. R. Davies, 'The Peoples of Britain and Ireland 1100-1400. I. Identities', Transactions of the Royal Historical Society, Vol. 4 (1994), pp. 1-20. Michael Prestwich, Plantagenet England: 1225-1360 (Oxford University Press, 2007).