Ancient Greek mythology is a vast and fascinating group of legends about gods and goddesses, heroes and monsters, warriors and fools, that were an important part of everyday life in the ancient world. Greek myths explained everything from religious rituals to the weather, and gave meaning to the world that people saw around them. While many of these myths are fanciful tales, such as the legends of greedy King Midas or heroic Hercules, other stories like the Trojan War epic have a basis in historical fact.

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There is no single original text, like the Christian Bible or the Hindu Vedas, that introduces all Greek myths’ characters and stories. Instead, the earliest Greek myths were part of an oral tradition that began in the Bronze Age, and their plots and themes unfolded gradually in the written literature of the archaic and classical periods of the ancient Mediterranean world.

The poet Homer’s 8th-century BC epics, The Iliad and The Odyssey, for example, tell the story of the Trojan War as a divine conflict as well as a human one. They do not, however, bother to introduce the gods and goddesses who are their main characters, since readers and listeners would already have been familiar with them.

Did you know? Many consumer products get their names from Greek mythology. Nike sneakers are the namesake of the goddess of victory, for example, and the website Amazon.com is named after the race of mythical female warriors. Many high school, college and professional sports teams (Titans, Spartans and Trojans, for instance) also get their names from mythological sources.

Around 700 BC, the poet Hesiod’s Theogony offered the first written cosmogony, or origin story, of Greek mythology. The Theogony tells the story of the universe’s journey from nothingness (Chaos, a primeval void) into being, and details an elaborate family tree of elements, gods and goddesses who evolved from Chaos and descended from Gaia (Earth), Ouranos (Sky), Pontos (Sea) and Tartaros (the Underworld).

Later Greek writers and artists used and elaborated upon these sources in their own work. For instance, mythological figures and events appear in the 5th-century plays of Aeschylus, Sophocles and Euripides and the lyric poems of Pindar. Writers such as the 2nd-century BC Greek mythographer Apollodorus of Athens and the 1st-century BC Roman historian Gaius Julius Hyginus compiled the ancient myths and legends for contemporary audiences.

READ MORE: What Was the Trojan War?

At the center of Greek mythology is the pantheon of gods and goddesses who were said to live on Mount Olympus, the highest mountain in Greece. From their lofty perch, they ruled every aspect of human life. Olympian deities looked like men and women (though they could change themselves into animals and other things) and were — as many myths recounted — vulnerable to human foibles and passions..

The twelve main Olympians are:

Other gods and goddesses sometimes included in the roster of Olympians are:

Greek mythology does not just tell the stories of gods and goddesses, however. Human heroes — including Heracles (aka Hercules), the adventurer who performed 12 impossible labors for King Eurystheus (and was subsequently worshipped as a god for his accomplishment); Pandora, the first woman, whose curiosity brought evil to mankind; Pygmalion, the king who fell in love with an ivory statue; Arachne, the weaver who was turned into a spider for her arrogance; handsome Trojan prince Ganymede who became the cupbearer for the gods; Midas, the king with the golden touch; and Narcissus, the young man who fell in love with his own reflection — are just as significant. 

Monsters and “hybrids” (human-animal forms) also feature prominently in the tales: the winged horse Pegasus, the horse-man Centaur, the lion-woman Sphinx and the bird-woman Harpies, the one-eyed giant Cyclops, automatons (metal creatures given life by Hephaestus), manticores and unicorns, Gorgons, pygmies, minotaurs, satyrs and dragons of all sorts. Many of these creatures have become almost as well known as the gods, goddesses and heroes who share their stories..

READ MORE: 6 Mythical Monsters

The characters, stories, themes and lessons of Greek mythology have shaped art and literature for thousands of years. They appear in Renaissance paintings such as Botticelli’s Birth of Venus and Raphael’s Triumph of Galatea and writings like Dante’s Inferno; Romantic poetry and libretti; and scores of more recent novels, plays and movies..