Answer + Explanation:
This is true! Many early civilizations believed in the afterlife and burial sites showed proof of this. I don't know how early you are looking at, but it is very common and popular within Ancient Greek and Ancient Eygptian cultures.
A famous myth in Ancient Greek was Charon, the boatman on the River Styx, which transported people to the Underworld. Upon burial, people would bury the dead with one obulus, a low-value coin, to cross the River Styx, as it was considered Charon's payment. The Greeks belived souls who could not pay were forced to wander the banks of the river on the ''Earth'' side, haunting those they left behind for at least a hundred years.
As for Eygpt, The ancient Egyptians had an elaborate set of funerary practices that they believed were necessary to ensure their immortality after death. These rituals included mummifying the body, casting magic spells, and burials with specific grave goods thought to be needed in the afterlife. In tombs, you could find artifiacts like Scarab Beetle charms and maps of the underworld.
