From "Ancient Origins" magazine I found out about the language of the Vikings. It was called Elfdarian. That sounds mystic doesn't it? At the present time, only about 3000 people can speak it and that is in one village in Sweden.
Speakers of Swedish, Danish and Norwegian can carry on a simple conversation with each other but none can understand Elfdarian.
As a final point. From the beginning of time, there has been about 30,000 different languages.