Linguistic Aspects of Worldbuilding

In fantasy and science fiction, some degree of world-building is essential. In fact, if you start out without doing some world-building type planning, you may end up writing a world that is a clone of Narnia, Valdemar, Middle-Earth or Darkover without intending to.

A centrally important aspect of world-building is language. You don't have to do what J. R. R. Tolkien did and construct languages for your fantasy world. But your novel will have characters and places, and those characters and places will have names. You want those names to add to
the realism of your fictional world and not distract from it.

Most of us choose an existing language as a model. Celtic languages and older forms of English are particularly popular. If your fantasy is set in what is essentially the past, this can be a good approach.

But if you want your world to be a little different, you might choose to make your names/words a little different from your source. You might replace letters with somewhat-similar sounds--- such as replacing 'd' with 't' or 'th' or shifting vowel sounds.

If you are using Celtic, one method is to write the words/names as they are pronounced, not as they are traditionally spelled. Irish names particularly are often spelled strangely, and respelling them is helpful to the reader as well as making it seem like a slightly different Celtic language, unlike the real ones of our world.

Sometimes words and name elements from different cultures are combined, as if  the language is that of a composite culture. If your world is not based on any Earth culture, picking two unrelated and uncommon languages and combining elements to create appropriate words/names can be a good strategy.

If you are writing a future world in science fiction, you must make sure character names don't contradict elements of your culture. If writing a world in which Christianity and related religions have long ago died out and been forgotten, don't give your characters Biblical names. (Use a good name book to detect name origins.)

Place names, on the other hand, usually are old and little influenced by the current cultural trends. Sometimes they are from other cultures--- as the many names of US cities which are derived from Indian words. Often the language has changed so much since a place was named that to the inhabitants it might as well have been named in a foreign language.

If you have hopes that your fantasy novel will continue to be read many years from now, avoid giving your characters new-and-faddish names. Such names often age quickly. Names like Mildred and Ethel were once wildly popular, but now most people think of them as the names of people's elderly aunts. While names like John and Mary are eternal classics, and even now no one will blink at a fantasy-world warrior named John.