How does A civilization in a mountain valley for several hundred years developing its own language isolation nearby such probably has been?

Isolation: It is possible for a civilization to exist in a mountain valley for several hundred years, developing its own language in isolation. Here's how it could happen:

Geographic Isolation: The mountain valley provides a natural barrier that separates the civilization from neighboring cultures and languages. The mountainous terrain makes it difficult for outsiders to reach the valley and for the inhabitants to venture out.

Limited Contact with Outsiders: Due to the geographic isolation, there may be limited contact with other communities or civilizations. This lack of interaction reduces the influence of external languages on the local language.

Cultural and Linguistic Preservation: The isolation allows for the preservation of cultural traditions, customs, and language. The civilization can develop its own unique ways of life and communication, distinct from neighboring regions.

Language Evolution: Over time, the language spoken by the civilization evolves naturally. It may incorporate words and influences from the surrounding environment and experiences of the people. However, due to the isolation, the language remains relatively free from external influences.

Oral Tradition: Since writing may not be widely practiced in an isolated civilization, the language is primarily transmitted orally from one generation to the next. This oral tradition contributes to the preservation and evolution of the language.

Divergence and Distinctness: As the language evolves in isolation over several hundred years, it can diverge significantly from the original language or languages from which it originated. This divergence leads to the development of a distinct language unique to the civilization.

It's important to note that such scenarios of complete isolation are rare, as civilizations often have some form of interaction or influence from neighboring cultures. However, the concept of a civilization developing a unique language in isolation does provide an interesting perspective on the factors that contribute to linguistic diversity.