The effect of the enduring cultural supremacy of French on a hierarchical patterning of registers has been summed up well by Otto Jespersen: “It is impossible to speak or write in English about higher intellectual or emotional subjects or about fashionable mundane matters without drawing largely upon the French (and Latin) elements.”

This “division of labour” between the two elements of the English vocabulary may be described as Anglo-French diglossia. The term “diglossia” is applied to the situation, which exists in many speech communities, when some speakers under different conditions use two or more varieties of the same language.

In English, the Anglo-French diglossia manifests itself in the contrasting stylistic uses of the vocabularies derived from different etymological sources. Whereas native Anglo-Saxon words tend to be used informally and feature strongly in everyday speech and slang, the Romance (French and Latin) element tends to be cultural and technical, educational and commercial, and is associated typically with more literary and “high-brow” styles, more appropriate for written reports and formal discussions.

The functional differentiation between the native and the imported Romance layers of vocabulary has evolved over several centuries and reflected the need to accommodate the growing complexity of registers. In the period following the Conquest, the Anglo-French diglossia was overt and unconcealed, with the French of the Normans taking over the “elevated” uses and becoming the accredited language of the Court and administration.

Gradually, however, it began to give way to latent or “hidden” diglossia, as can be seen in the development of the Middle English “high style” – the term used by the rhetoricians of the Middle Ages to describe the literary style deemed proper for serious and elevated works. This particular style can be found occurring in English from about 1350 onwards, and in the fifteenth and early sixteenth centuries it flowered in a very elaborate and Latinate form called aureate. It may very well have been an attempt to fit English for some of the elevated duties that the language of the Normans was felt to have performed in the past.

It is also significant that in the period from the thirteenth to fifteenth centuries a large portion of the literature of England consisted of translations of French romance, and the native poetry was powerfully influenced by French models. It is only natural under these circumstances that a large number of French words should enter the English literary dialect through translation.