Is it a bird? Is it a serpent?

This book, by the director of Mexico's National Council of Culture and Arts, and a justly renowned historian, is far more than its title suggests.The god - or god-man - Quetzalcoatl ("feathered serpent") has gripped the western imagination ever since the first conquistadors, and has even spawned novels, such as The White God , a 19th-century romance by the same General Lew Wallace who gave us Ben Hur . Revered by the Aztecs as the culture-bearing deity who had brought them all of the arts, and patron of the priestly class (significantly, the two supreme pontiffs of the Aztec state bore his name as title), Quetzalcoatl was surrounded in mythology and ritual in incense and piety. He was the very antithesis of the supreme god of the Aztec people and state, Tezcatlipoca ("smoking mirror"), the much-feared patron of the warrior class and of sorcerers, and the god of the night sky.

Quetzalcoatl the god is inextricably entwined in the Aztec mind with a probably mythical king of Tollan, the ancient Toltec capital (identified with Tula, in the state of Hidalgo), held by the Aztecs to be the ultimate source of their civilisation. This individual, named in the chronicles as Ce Acatl (a calendrical notation) Topiltzin Quetzalcoatl, was supposedly fair-skinned - hence Wallace's title - and bearded; he had lost his throne to his adversary, the dread Tezcatlipoca, and disappeared to the east, some day to return for the redemption of his people. The invading Spaniards were quick to seize and embroider upon this story, eager to convince the native lords that the white, bearded Hern n Cortes was, in fact, Quetzalcoatl, returned from the east to claim a kingdom that was his by right.

There is a powerful shamanic element in the religious systems of Mesoamerica, as manifested in the pairing of powerful gods and even politico-religious leaders with supernatural counterparts, alter egos or doppelgängers , if you will. Quetzalcoatl's was a rattlesnake covered with resplendent green quetzal feathers. As Enrique Florescano says, this avatar expressed the ancient Mesoamerican idea of the unity of opposites: the serpent being a creature symbolising the fecund earth and the netherworld, and the bird the sky and the air. All these aspects of this multi-faceted god have been well known to scholars for two centuries. But Florescano points to another, and deeper, meaning to this deity. Quetzalcoatl plays a highly significant role in the creation stories that have come to us from both the Aztecs and another people of the late pre-conquest period, the Mixtecs of Oaxaca. In several of these, he has mighty tasks to perform, as the penultimate of a series of world creations and destructions comes to an end, and a new universe is about to form. And both of these involve the origins of the human race. The sky of the previous world having fallen upon the earth, it must be raised once more. This having been accomplished, Quetzalcoatl makes a dangerous journey to the underworld to rescue the bones of humankind, and he creates people once again by scattering his own blood over the remains. But what are they to eat? Because the gods have hidden all of the plant foods upon which we and our ancestors might subsist inside the Mountain of Sustenance, Quetzalcoatl changes himself into an ant, enters the mountain, and steals the precious maize seeds. Quetzalcoatl is thus not only a culture hero, but the provider of life itself, and of all that makes us human.

Florescano shows that this concept goes far back into the Mesoamerican past, in fact to the Olmec civilisation of Mexico's Gulf coast, where truly effective maize agriculture began. Incised jade celts dating to the period 900 to 400 BC clearly show the plant, along with its ears, springing from a cleft in the head of an Olmec divinity ancestral to the maize gods of later cultures. Recent epigraphic and iconographic research has demonstrated that the basic lineaments of a death-and-resurrection story preserved for us in the 16th-century Maya-Quiche epic, the Popol Vuh ,played a central role in the classic Maya civilisation of the lowlands. In this great myth, the young maize god, known in the Popol Vuh as Hun Hunahpu and in hieroglyphic texts as Hun Nal Ye or "First Father", is defeated in a magic ball-game played in the netherworld; as a result, he is beheaded by its sinister gods. Eventually his two sons, the Hero Twins, descend again into the lower regions, resuscitate their father and bring him once more to the earth's surface. In triumph, the twins rise to the sky to become the sun and the moon.

This story permeates Maya art and religious iconography, since it is basically the story of maize, the Maya (and Mesoamerican) staff of life. Just before the outset of the rainy season, the farmer makes a hole in the ground with his digging stick, and by placing the dry, seemingly dead seed in it, metaphorically sends the maize kernel into the netherworld. Resurrection takes place when the rains come, and the new, green shoot appears to break from the earth's surface.

Florescano's book is a survey, guide to and analysis of the fundamental mythologies of Mesoamerica through time and space, with the death and resurrection of maize as a central theme. He has shown how an understanding of these great themes can reveal the meaning of some of the greatest ancient monuments. Temple 22, at the Classic Maya site of Copan, for example, is patently the Mountain of Sustenance or "First Mountain", and it is dedicated to the maize god, as the lovely, youthful, limestone sculptures which once adorned its summit testify (one of these is a British Museum treasure).

Quetzalcoatl-like gods appear at every stage of Mesoamerican culture history, continually reinterpreted to fit the circumstances of the time. For instance, when the classic states atrophied or were destroyed over much of Mesoamerica during the 9th and 10th centuries AD, the rule of single, powerful kings became a thing of the past, and migratory, samurai-like bands held sway. In this militaristic climate, the Quetzalcoatl story was refitted so that these upstarts could claim Tollan (the place of reeds) as their original homeland, and the man-king Ce Acatl Quetzalcoatl as their paladin.

But the concept of the divine provider of human sustenance was forever central, as it is in many other cultures around the world. In his final chapter, Florescano embarks upon a tour of the comparable agricultural deities and cults of Europe and the Middle East (the most striking parallels exist between the Mesoamerican maize god complex and the Osiris cult of ancient Egypt, both with their themes of death and resurrection).

Florescano has written an outstanding work, synthesising highly complex data from many sources. He has not, however, always been well served by his translator, who all too often displays unfamiliarity with the subject matter. Such errors include using the word "truss" when "loincloth" is meant; maize "husk" for maize "ear"; "cohabited" for "coexisted"; "Borbonic Codex" for "Codex Borbonicus"; and many others. These I hope will be corrected in later editions. Best used in conjunction with The Gods and Symbols of Ancient Mexico and the Maya by Mary Miller and Karl Taube (1993), The Myth of Quetzalcoatl is a brilliant introduction to the underlying themes of Mesoamerican religion, from 1200 BC to the Spanish invasion, and can be read with profit by all those interested in the mental systems of some of the world's most fascinating civilisations.

Michael D. Coe is emeritus professor of anthropology, Yale University, United States.