The use of Latin alongside everyday languages in medieval Britain is one continuation of a long and complex linguistic heritage.
Latin, as the everyday language of the ancient Romans, first spread across Europe with the growth of Roman civilization and the expansion of the Roman empire. When the empire came to an end in Western Europe in the fifth century AD, the Latin language did not simply die out. Throughout its history Latin had been evolving as a living language, and as a native everyday language it continued to evolve, increasingly differently in different parts of Europe, turning ultimately into the modern Romance languages, which include Italian, Spanish, Portuguese, French, and Romanian.
Alongside the development of the everyday native languages across Europe, Latin survived as a ‘second’ or non-native language used in a wide variety of functions, mainly in writing. In coexisting with its users' everyday languages, the Latin language continued to change and evolve throughout the Middle Ages under the influence of their grammar and especially their vocabulary, which was frequently ‘borrowed’ into medieval Latin. (The process of borrowing in situations of language contact is extremely common in general, as can be seen, for instance, in the extent of English borrowing from French in the years following the Norman Conquest.)
In Britain the historical linguistic situation was slightly different from that in the parts of Western Europe where the modern languages are directly descended from Latin. The native languages in Britain through the early medieval period (before the Norman Conquest) were not descendants of Latin, being instead Celtic or Germanic in origin. However, the prestige of Latin meant that nonetheless throughout the Middle Ages it was still an important ‘second’ language in Britain, alongside the native languages. (Latin from Britain in fact played a crucial role in redefining continental Latin during the ‘Carolingian Renaissance’ in the ninth century.)
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