* Ancient civilizations: Like the Ancient Egyptians, Sumerians, or Greeks, who each had their own distinct languages.
* Prehistoric humans: This group is even more diverse, with multiple language families developing over tens of thousands of years. We have no written records from this period, so we can only speculate about their languages.
* Specific groups within a time period: For example, "archaic Greeks" refers to a specific time period in Greek history, and they spoke different dialects of Ancient Greek.
To answer your question accurately, you need to be more specific about which archaic people you're interested in.
For example, if you're asking about the language of the Ancient Egyptians, the answer is Ancient Egyptian, a language that's now extinct.
If you're asking about the language of prehistoric humans, the answer is we don't know. We have no surviving records from that time, and we can only study the development of language through archeological evidence and comparing modern languages.
Please give me more information about the specific group you're curious about, and I can give you a more precise answer.