I'm going to share 2 works by Ancient Greek authors, Hesiod and Thucydides, because that's what I know and can reference off the top of my head—

First let's look at a very ancient source. Around 700 BCE lived a poet named Hesiod who wrote two well-known works, the Theogony, an account that sought to establish the lineage and relationships between all the different titans, gods, demigods and creatures from various regions' mythologies, into the usual canon of Greek mythology we think of today. The other was Works and Days, an instructive guide on how to live a moral life and how to effectively run a farm, framed as a story where Hesiod is lecturing an idle brother.

Part of Works and Days is also explaining things like why strife exists and why life requires hard work, and here we get into an account Hesiod shares of prehistory: He tells of 5 Ages, the Golden Age, Silver Age, Bronze Age, Heroic Age, and the Iron Age, which was the age his contemporary Greeks lived in. I won't copy/paste the whole section here, but it's lines 109-201 of Works and Days, here's a link if you want to read it. It's a much more mythological than historical account, implying that the major shifts in human civilization are the work of direct intervention and even re-creations of humanity by Zeus, and that basically the first creation in the Golden Age was amazing and there was no hardship or war or anything, but then by the Bronze Age everyone was using bronze weapons and was incredibly warlike. Then the Heroic age is the time when the Homeric epics and the Trojan war and mythological stories took place, when Zeus made a generation of demigods that went around everywhere. And finally the present, where everything sucks:

Thereafter, would that I were not among the men of the fifth generation, but either had died before or been born afterwards. For now truly is a race of iron, and men never rest from labour and sorrow by day, and from perishing by night; and the gods shall lay sore trouble upon them. But, notwithstanding, even these shall have some good mingled with their evils. And Zeus will destroy this race of mortal men also when they come to have grey hair on the temples at their birth. The father will not agree with his children, nor the children with their father, nor guest with his host, nor comrade with comrade; nor will brother be dear to brother as aforetime. Men will dishonour their parents as they grow quickly old, and will carp at them, chiding them with bitter words, hard-hearted they, not knowing the fear of the gods. They will not repay their aged parents the cost their nurture, for might shall be their right: and one man will sack another's city. There will be no favour for the man who keeps his oath or for the just or for the good; but rather men will praise the evil-doer and his violent dealing. Strength will be right and reverence will cease to be; and the wicked will hurt the worthy man, speaking false words against him, and will swear an oath upon them. Envy, foul-mouthed, delighting in evil, with scowling face, will go along with wretched men one and all. And then Aidos and Nemesis, with their sweet forms wrapped in white robes, will go from the wide-pathed earth and forsake mankind to join the company of the deathless gods: and bitter sorrows will be left for mortal men, and there will be no help against evil.

It's definitely not historical, as the Golden and Silver age men are more like mythological creatures and both became spirits when their ages ended, but it is an interesting view of the past, especially the idea that things used to be better and that the Iron Age is the worst.

But, let's jump forward to 400 BCE, 300 years later, to Thucydides, author of The History of the Peloponnesian War, which takes a much less fantastical approach to the idea of what came before. It doesn't go all the way back to the dawn of humanity, but it's probably more along the lines of what you're looking for. From Thucydides 1.2-1.7, it tells Thucydides' conclusions on how the country of Greece and the idea of city-states arose from stateless and even town-less migratory tribes a couple thousand years before.

The country which is now called Hellas [Greece] was not regularly settled in ancient times. The people were migratory, and readily left their homes whenever they were overpowered by numbers. There was no commerce, and they could not safely hold intercourse with one another either by land or sea. The several tribes cultivated their own soil just enough to obtain a maintenance from it. But they had no accumulations of wealth, and did not plant the ground; for, being without walls, they were never sure that an invader might not come and despoil them. Living in this manner and knowing that they could anywhere obtain a bare subsistence, they were always ready to migrate; so that they had neither great cities nor any considerable resources...

The feebleness of antiquity is further proved to me by the circumstance that there appears to have been no common action in Hellas before the Trojan War. And I am inclined to think that the very name was not as yet given to the whole country, and in fact did not exist at all before the time of Hellen, the son of Deucalion; the different tribes, of which the Pelasgian was the most widely spread, gave their own names to different districts. But when Hellen and his sons became powerful in Phthiotis, their aid was invoked by other cities, and those who associated with them gradually began to be called Hellenes, though a long time elapsed before the name prevailed over the whole country. Of this Homer affords the best evidence; for he, although he lived long after the Trojan War, nowhere uses this name collectively, but confines it to the followers of Achilles from Phthiotis, who were the original Hellenes; when speaking of the entire host he calls them Danaans, or Argives, or Achaeans. Neither is there any mention of Barbarians in his poems, clearly because there were as yet no Hellenes opposed to them by a common distinctive name. Thus the several Hellenic tribes (and I mean by the term Hellenes those who, while forming separate communities, had a common language, and were afterwards called by a common name), owing to their weakness and isolation, were never united in any great enterprise before the Trojan War. And they only made the expedition against Troy after they had gained considerable experience of the sea.

You can see that this wasn't a knowledge passed down to him from the days of Hesiod and before, but an idea he and other contemporary educated Greeks arrived at through studying their oldest texts.

Minos is the first to whom tradition ascribes the possession of a navy. He made himself master of a great part of what is now termed the Hellenic sea; he conquered the Cyclades, and was the first coloniser of most of them, expelling the Carians and appointing his own sons to govern in them. Lastly, it was he who, from a natural desire to protect his growing revenues, sought, as far as he was able, to clear the sea of pirates.

(Now this is getting into history that was passed down as oral mythology— everyone knows the story of King Minos and the Minotaur on the island of Crete, but modern Europeans thought he and his civilization were probably totally mythological until the 20th century, when the palaces of the Minoan civilization were discovered (which we in modern times named after Minos).)

For in ancient times both the Hellenes, and those Barbarians, whose homes were on the coast of the mainland or in islands, when they began to find their way to one another by sea had recourse to piracy. They were commanded by powerful chiefs, who took this means of increasing their wealth and providing for their poorer followers. They would fall upon the unwalled and straggling towns, or rather villages, which they plundered, and maintained themselves chiefly by the plunder of them; for, as yet, such an occupation was held to be honourable and not disgraceful... On land also neighboring communities plundered each other; and there are many parts of Hellas in which the old practices still continue, as for example among the Ozolian Locrians, Aetolians, Acarnanians, and the adjacent regions of the continent. The fashion of wearing arms among these continental tribes is a relic of their old predatory habits.

For in ancient times all Hellenes carried weapons because their homes were undefended and intercourse was unsafe; like the Barbarians they went armed in their every-day life. And the continuance of the custom in certain parts of the country indicates that it once prevailed everywhere. The Athenians were the first who laid aside arms and adopted an easier and more luxurious way of life...

In later times, when navigation had become general and wealth was beginning to accumulate, cities were built upon the sea-shore and fortified; peninsulas too were occupied and walled-off with a view to commerce and defence against the neighboring tribes...

And it continues in this fashion. I abridged it a bit, but you can read the full text from the link at the top. It's not going back to, like, stone age prehistory, or before the invention of the idea of agriculture, but it definitely describes a time before these migratory tribes that could become Greeks had writing (though the Minoans had writing a thousand years before the Greeks picked it up).

There are many more variations on the ideas about how humanity started from various philosophers. And then I'm sure there are, say, Egyptian equivalents to Hesiod's more mythological approach, and I'm sure later Roman historians wrote texts along the lines of this passage from Thucydides. I hope to find out more from other users here.

In book six of The Histories Polybius builds on Plato and Aristotle's framework of political construction to go into a diversion about the 'natural state of man.' It's a brief passage wherein he observes how either following societal collapse or prior to the formulation of a society, humans, like other animals, tend to gather in groups. Inevitably one individual of intelligence and/or strength emerges as a leader and so on through kingship, oligarchy, democracy, mob, repeat.

The passage is interesting to me (in relation to your question) because if nothing else it reveals how Polybius felt himself to be (correctly) in a highly developed civilization that was well beyond a prehistoric state as we conceive it.

There was no archaeology whatsoever in the modern sense but it's clear that the lack of specific historical information notwithstanding they understood conceptually in the same manner that we do that there was a time before "all of this."

It may be an obvious or simple point, but I still find the way it reminds me that these were living breathing humans just like me to be continually profound.