For example, would an educated Greek aristocrat see Odysseus as a universal symbol or is that strictly a modern interpretation? Why were these myths considered so valuable by ancient Athenians?
As a modern reader, it's hard for me to see the importance of the Descent of Inanna, Epic of Gilgamesh, Beowulf, and similar works unless analyzing them from a Jungian perspective. Were these stories just seen as entertainment, as embodiments of transcendent aspects of the human experience, or somewhere in between? Do we even know?
Posting here rather than in a mythology or literature subreddit because I'm interested specifically in the role these works played in society and day-to-day life. Thank you in advance, and thank you most of all for tolerating my ignorance.
I can't speak for any of the Classical Epics but Beowulf was certainly more than pure entertainment. Although written in the eighth century (NB There is much disagreement over this) the practices and events in the epic pre-date it by far. Arguably, Beowulf is an origin myth - a strange amalgamation of true historical events and mythical characters. For example, that King Hygelac was killed in an ill-fated raid on Frisian shore (lines 1204-1216) is backed up by several other sources, including the Gregorii episcopi Turonasis Historia Francorum (History of the Franks) by Gregory of Tours. Hygelac (whom he calls Chlochilaichus), he says, won a battle at Ravenswood in 510AD before being killed attacking the Frisians in 521AD. Similarly, on examining family trees of major houses, like the Wuffing house (Potentially the family of Sutton Hoo) mention many of the kings of Beowulf. Some of the major characters, such as Hrothgar also recur within other contemporary texts such as Widsith and the Norse Sagas. There is evidence to suggest that Hrothgar, Ongentheow, Haethcyn, Onela and Heardred were all historical characters. Perhaps the most notable name we find in Beowulf is that of Hengest. Hengest, who succeed Hnaef as leader of the Half-Danes avenges his death by killing fin, king of the Frisians. This Hengest, who appears in the Finnesburgh Fragment is quite possibly the same Hengest who came to England in 449AD at the request of King Vortigern in order to fight the Picts; the same Hengest who, as reported in The Anglo-Saxon Chronicle, then performs a treacherous volte-face, turning on Vortigern and the Britons before founding the kingdom of Kent. This Hengest would, to the Anglo-Saxons, be a legendary figure of huge interest, comparable only perhaps to the American Founding Fathers or of the titular character of the Aeneid. So, I would argue that although, of course, Beowulf is a guide on heroism and kingship, it is also a socially binding origin myth for the Scandinavian migrants that settled Britain. First and foremost, however, as an oral composition (which it most likely is), its primary function must be seen as entertainment. I hope this answered at least part of your question!