There are many things you need to consider when writing historical fiction; it has peculiarities unique to the genre (see How to deal with Historical Research). Language is one of these. Your reader wants to believe they have been transported to the past and the language you use is how they move through time into your chosen era.
People in the past did not speak as we do. Native tongues differed (and there were more languages spoken than today) and even those who spoke the same natal tongue often could not understand each other as dialects were much more diverse and local phrases in greater use. These days, modern technology draws us closer together, despite distance, and language both narrows and spreads.
If you choose to write in authentic historical language, I would hazard a guess that you have a degree in the subject. However, if you write in Chaucerean Middle English the only readers you are likely to have are other people with degrees in Middle English. You need to convey a spirit of the past without making it unintelligible to the modern reader.
Regency novelist Georgette Heyer masterfully used language to let her reader know they were entering a different era. She littered dialogue with different words and phrases, using different ones for different social classes. She became such a…
