Are there any languages; besides, Latin, which are no longer spoken fluently?
There are many dead languages, and many languages which have changed so much that nobody speaks it fluently any more. All languages change with time–you could only read Chaucer with a special dictionary, and he wrote in English just 200 years earlier than Shakespeare. You couldn’t read the Robin Hood legends at all. Some languages change faster, some slower, but all of them become incomprehensible eventually. When a people group migrates, or is conquered, their language may simply disappear, as has happened with many Native American languages, or ancient Egyptian.
