What does the "Iliad" reveal about the earliest days of Greek culture?
Among other things, The Iliad shows the importance of war in the ancient world. War wasn't looked upon as a necessary evil; it was essential to defend the prestige of one's homeland as well as individual honor. War was a proving ground in which men displayed courage on the field of battle, potentially turning themselves into heroes whose names would live on in fame for centuries. The ancient Greeks lacked any sense of modern individuality; people were defined almost exclusively by the roles they played in society. Fighting in the seemingly endless wars as a soldier was one such role, the most important one of all.
The role of women in ancient Greece is starkly revealed by The Iliad. Women, of course, were not allowed to participate in battle, so in the poem they're reduced to the state of wailing, anxious bystanders, fretting that their menfolk will be killed and their families taken as slaves. They had good reason to be worried. After the fall of Troy, most of the civilians were either slaughtered or forced to become the Achaeans' slaves. Women were regarded as little more than spoils of war, objects looted from the enemy to be either ransomed or kept as concubines. Indeed, we can get a pretty good idea of how the ancient Greeks regarded women if we consider that the Trojan War as a whole was blamed on the infidelity of a woman, Queen Helen of Sparta, who left her husband, Menelaus, for Prince Paris of Troy.
The Iliad offers us a window into many key tenets of early Greek society. During the time depicted in this poem, bronze was still the strongest metal. Multiple kings ruled small kingdoms without any centralized government to prevent wars breaking out between small factions. The depiction of women in the poem also helps us understand that they were still viewed as chattel, without agency, in this society.
Warfare was the aim of the ruling classes; piracy was common and was seen as a valid way to make a fortune. However, despite this, guest rights and hospitality conventions were sacred to the early Greeks. The true issue underlying Paris's abduction of Helen was that Paris broke the rules of hospitality; Helen herself was a possession and stealing her represented a challenge to the accepted rules between guest and host.
At this stage of Greek development, there was no concept of a happy afterlife. As such, the only way to live forever was to establish a reputation in order to avoid dying in obscurity, the worst fate.
There are quite a number of ways to approach this question. We see the importance of gods in the lives of the Greeks. We also see their strong belief in fate. Even the gods cannot control fate. Humans are controlled by the gods and fate and seem to have little control over the outcome of things. They look for signs to guide them. They do not always obey the signs but are aware of the existence of those signs. The other aspect you could focus on is the role of women who are seen as nothing more than trophies to be obtained and owned.