changing language over 1,000 years

Not an expert in Languages...
If you are looking for 1000 years you are closer to Anglo-saxon and Norman [and Latin]. I'd avoid them if I could
If it is not actually English you are talking about, then you could make illusions to Arabic and Latin. AFAIK Arabic has adapted over the last 1400 years but old or new it can still be read and understood. It is the local regional spoken accents that make the difference.
Latin has been used by the Catholic Church for about the same time.
English has changed so much because it is constantly taking in parts of other languages, French, German, Urdu, Hindi, Swahili, Dutch to name a few.

 

As yourself admit, and like the previous replies have already pointed out, trying to use such a language for your mythical creatures could be problematic on several levels. What can you do about this then? I happen to have a few ideas you might like to try:

• Describe that language from the protagonist's point of view. Obviously, the protagonist won't know at first what language it is, but he/she could describe how it sounds to him/her and even recognize some words in their first attempt of communication.
• Jump between the point of view of the protagonist and the creature's. That way you can play with how the creature perceives the world it has been awaken into and its thoughts about the protagonist and their relationship. This would effectively turn the creature into your other main protagonist, rather than just the being used by the protagonist to have his/her adventure.
• When you happen to have several mythical beings talking to each other, describe the situation so the reader can understand that you're switching from the protagonist language to the creatures one.
• Don't make the creatures learn the protagonist's language fast, doing just the opposite forces the protagonist to try harder to understand those beings and, by extension, strengthen his/her relationship with them. Also, think from the point of view of the creatures, you can use their degree of interest in the human language to show their thinking about the world they have been awaken into.
• From time to time, you can throw a few simple sentences in the creature's language just for spicing up a scene, or to enhance the emotional effect of actions or decisions done by a mythical creature. I'm referring to something like a battlecry, or chant, or anything not too complicated.
• You might also like to consider the cultural and linguistical differences among different mythical creatures. Beings from different regions, races, or even different time periods could have completely different languages and cultural traits. You might like to explore this to enhance the mistery around those creatures. For instance, you could have a bunch of creatures that have been sealed for five thousand years for some reason or other, and in the course of the adventure, your characters have to deal with them. The protagonist might show his smarts by finding some way to help his/her mythical companion communicate with those ancient beings.

 

skip.knox has raised a very interesting point that is often under-appreciated. Even within a particular language there can be many considerable differences. An obvious case is the difference between Portuguese as spoken in Portugal and Portuguese spoken in Brazil.

In most Commonwealth countries the local versions of English tend to incorporate words from local or indigenous languages into their everyday speech. In India Hindi words are incorporated into their English. In New Zealand we incorporate Maori words into our English. Add collequialisms, the different meanings of the same words within many cultures and regional accents and you quickly come to understand why the English spoken in some parts of the world is incomprehensible to a lot of English speakers from other parts.

A lot can happen to a language in the space of a thousand years. Chinese has been around for over three thousand years but a person from three thousand years ago would find a lot of words and phrases used by a typical Chinese person in 2020 incomprehensible and vice versa. However, it would not be impossible for them to have a conversation. There would be a lot of misunderstandings, confusion and offense caused that could be used for both comic relief or for creating very dangerous situations, especially if cultures and societies have changed considerably over the thousand years in question.

 

I think in dialogue it's comparable to using dialect. Don't overdo it, is the general advice, as it is even difficult to read by people from the region, because there is no agreed spelling.
Maybe use a word here and there to convey the flavour. Or use daily stuff that was common thousand years ago but has disappeared. In my youth I watched Catweazle on the telly and maybe you could use that concept to remind the reader constant that the creature cannot know what happened the last 1000 years ...

 

Hi: Most have already said it, but for my personal taste it would depend highly on the rest of your world: How advanced the society is and what has happened over the past 1000 year will make a big impact on the language.

The language may not have changed that much if it was a stable government, on an island, where they hate trade and have a highly efficient written language and education system. If the books are also a thousand years old and everyone can still read it.. then... no problem.

If its a war torn area with little education and constantly changing rulers etc etc... then 1000 years and the language is probably completely unrecognizable: maybe not even in the same family as the old language was lost a long time ago.

So my advice is: Don't start with the language problem, start with what has happened over the last 1000 years and what is the more likely scenario? Then find how that makes the world richer.

 

You can just note that creature starts off speaking weirdly but quickly adapts. After all, Croatian language from 1 000 years ago would be funny but still understandable (if only barely so) to speakers today. So you don't need to make up language, or spend too much time noting the difference.

 

I am a linguist working professionally with language change. Some languages change a lot over 1000 years - enough to be mutually unintelligble, others change very little. Whether the change is quick or slow seems to depend mostly on whether society changes a whole lot or a little in the period, and on whether the culture and society where it is spoken interacts with and is influenced a lot by other cultures and societies or not.

But in a fantasy novel, it really depends on how you think of language: Do the people in your world actually speak modern english, or do they have their own languages that you as the author just "translate" into modern English?

You could show the difference by noting that the character that has woken up into a new world has difficulty understanding some new words - if somethings in society has changed (technologica inventions, new social institutions etc.) then they will not know what the new words describing them mean.