When Christopher Columbus sailed west, he found a New World, an enormous realm of land and peoples that had been effectively isolated, unknown, and even unsuspected by most of the peoples of the Old World. Almost as soon as the first contact was made, on the little island of San Salvador in the Bahamas, speculations began on who these strange, bronzed, black-haired savages might be. Columbus himself thought them “Indians,” inhabitants of the East Indies, and felt confident he was not far from Japan and might even be in the lands of the Great Khan of Cathay. By the time the Pacific Ocean had been discovered by the European explorers and the full immensity and isolation of the North and South American continents realized, the mystery of the American “Indians” was redoubled.

Following closely on these great discoveries was the Spanish conquest of Mexico and Peru. The contemptuous dismissal of the Indians as savages soon turned to an almost universal admiration as accounts, most of them accurate and detailed, of the great civilizations filtered back to European philosophers and scholars. Even the hard-bitten Spanish conquistadors were awestruck at the size and splendor of the empires they were smashing to ruins. Consider the letter that Cortés sent to his emperor, Charles V (dated October 30, 1520), in an attempt to describe the wonders he had seen in the Aztec capital of Tenochtitlán, gleaming white on an island in the midst of a broad lake. It reads in part:

To give an account, Very Powerful Lord, of the greatness, and the strange and marvelous things of this great city of [Tenochtitlán] to Your Royal Excellency, and of all the dominions and splendor of Moctezuma its sovereign; of all the rites and customs which these people practice, and of the order prevailing in the government, not only of this city, but also of others belonging to this lord, much time and many very expert narrators would be required. I shall never be able to say one-hundredth part of what might be told respecting them, but, nevertheless, as far as I am able, I shall speak of some of the things I have seen, which although badly described. I know very well will cause much wonder, that they will hardly be believed, because even we, who see them here with our own eyes, are unable to comprehend their reality.

The early Spanish friars who came to Mexico were a gifted group of scholars, particularly the Franciscan missionaries who founded the College of the Holy Cross, in what is now Mexico City. One friar, Bernardino de Sahagún, wrote a great sixteenth-century encyclopedia on virtually all aspects of Aztec life as it was just before the conquest. By combining these works and some others written by the Aztec nobles with the eyewitness reports of the conquistadors, the society, politics, religion, and daily life of the Aztec civilization can be reconstructed.

The imperial city, Tenochtitlán, was so thoroughly destroyed by the Spaniards that hardly anything remains beneath Mexico City, the modern capital built upon its ruins. On the eve of the conquest, Tenochtitlán contained perhaps 60,000 people. In the center of the city was the Sacred Precinct, with lofty temples raised upon pyramids, dedicated to the worship of the innumerable gods of the Aztec people. The never-ceasing rituals, which included the heart sacrifice of vast numbers of war captives, were in the hands of a celibate clergy. Around the Sacred Precinct were the palace of the emperor, Moctezuma II, and those of his predecessors. Beyond this were the great houses of court nobles and administrators, and farther out yet, the dwellings of the freemen and merchants.

This was the administrative heart of an empire that reached from the Gulf of Mexico to the Pacific, with millions of people of diverse languages and cultures. Trade was one of the two principal foundations of the empire, and the daily markets of the Aztec capital were vaster than anything known to the Spaniards in the Old World; foodstuffs, luxury products from distant areas, and even slaves were bought and sold. The other pillar was conquest, and Aztec armies were feared all over Mesoamerica for their ferocity and skill at arms. Conquered states were quickly incorporated into the Aztec empire and forced to pay heavy tribute in food, weapons, and other goods for the support of Tenochtitlán.

But from where did the Aztec come? They say in their own histories that they were the last to enter central Mexico, to take over that vast, lake-filled valley where they built their mighty capital. According to them, they left an ancient homeland, Aztlán, located somewhere in western or northwestern Mexico, and wandered east following the image of the tribal god carried by four priests. The year was around CE 1168. They were by their own testimony semi-barbarians, but by the mid-fourteenth century, they had settled in the Valley of Mexico and began adopting the customs of their more civilized predecessors, whose descendants still controlled small city-states around the lake.

The Aztec, in fact, readily admitted that there had been a glorious empire before their own, ruled from another capital, Tula, by a people called the Toltec. This city, which according to traditional accounts was founded in the tenth century CE and destroyed in the twelfth, is described in enthusiastic terms by the Aztec. The Toltec were said to have been the finest craftsmen who ever lived, and there was nothing they could not do. They were ruled by a great king who took on the title of the Mesoamerican god Quetzalcóatl (Feathered Serpent), and his exploits were forever mixed with those ascribed to the god. This semilegendary Quetzalcoatl was ousted from power by the evil god Tezcatlipoca, Ruler of Life and Death, and forced to leave Tula, journey to the Gulf Coast, and cross to the land on the other side from where he was one day to return for the redemption of the Mexican people. That a Toltec ruler calling himself Feathered Serpent did actually make this trip and did, in fact, conquer the land on the other side of the Gulf - Yucatán - is known from the traditions of the Maya, who inhabited Yucatán.

So, as far back as the mid-tenth century, there is some kind of history, semilegendary though it is. It is reminiscent of the Song of Roland and other chivalric romances, historical in basis but thoroughly entwined with the poetry of legend. But the Spanish scholars of the colonial period, and their readers in Europe, wanted to know what lay behind this. What was the ultimate origin of the American Indians? The Aztec had an almost legendary remembrance of an earlier civilization, whose great ruins lay not too many miles from their capital: This was Teotihuacán; and beyond it, Tamoanchán, where Mesoamerican civilization first began.

History and legend ultimately helped little in unraveling the origin of the natives and their civilizations. Nor did the accounts of the Inca in Peru or of any other native people add much. Here in the New World, in the far-removed wilds of Mexico, was a people who had gods, temples, priests, incense, confession, and sacrifice; kings and palaces; books and writing. What more natural conclusion was there than to assume they were from the civilized regions of the Old World? The story of the ten lost tribes of Israel was tailor-made for such an explanation - the Indians were Jews.

Every conceivable voyage and migration account from the Old World, no matter how fantastic, was searched in the sixteenth to nineteenth centuries for clues to support this conclusion. The natives of the New World had come from Wales with the legendary King Madoc; they were Tartars from China (this one was not so far from the mark), and so on. Only a few scholars cautioned against such wild speculations, among them. José de Acosta, a Spanish missionary who proposed in 1590 that the American Indians were Asiatics who had crossed into North America by land from northeast Asia. But who would have dared to suggest, at a time when the earth itself was not thought to be more than 5,000 or 6,000 years old, migration might have happened over 40,000 years ago?

Not long after the conquest of 1521, travelers in colonial Mexico and Central America stumbled across remains of other, older civilizations. Teotihuacán, near Mexico City, had never, in fact, been forgotten, and its ruins are so imposing it is unlikely they ever could be. Moctezuma made an annual pilgrimage on foot to its immense Pyramid of the Sun. Besides Teotihuacán, the principal Mesoamerican civilization discovered in post-conquest times was the Maya.

The Maya, much alive at the time of Spanish contact, has never completely died out, surviving today in varying degrees of purity among approximately 2 million living Mayan-speakers. In the mid-sixteenth century, as now, they inhabited two areas: the northern part of the Yucatán Peninsula and the rough mountain country of Guatemala and Chiapas (in southeastern Mexico). All of the lowland jungle in between was an empty wilderness.

One of the most interesting and terrifying figures of colonial Mexico was the Franciscan Bishop of Yucatán, Fray Diego de Landa. Famed for allegedly destroying all the extant Maya books or codices in a great bonfire in the 1550s, he was nonetheless the man who set down on paper much of what is known of Maya civilization as it was just before the Spanish arrival. This manuscript was, however, lost to scholarship until rediscovered in the 1860s. Like numerous other friars, Landa noted that the flatland of Yucatán was dotted with ruins left by a previous civilization, and he did much to connect them with the ancestors of the living Maya. He was also fascinated by the Maya system of hieroglyphic writing and their complex calendar, and he left many clues for their subsequent decipherment.

Thus, the Maya were never truly unknown, but in the nineteenth century, two travelers first exposed to the world the glories of this ancient civilization. John Lloyd Stephens was an American lawyer, diplomat, and inveterate traveler, and his companion of two momentous journeys was Frederick Catherwood, an English artist and draftsman. The first trip, in 1839, took them, mainly on foot or by other primitive transport, into the fringes of the vast, deserted central area that proved to be full of abandoned Maya centers, as well as many of the ruins of Yucatán.

Then, in 1841, they returned to Yucatán for a more thorough reconnaissance. The descriptions of Stephens and the illustrations by Catherwood, which they published jointly in Incidents of Travel in Central America, Chiapas, and Yucatán, can hardly be surpassed for accuracy and for cool scholarship. They knew that the great archeological sites now ascribed to the Classic period were the works of Maya Indians, and not of Israelites, Welshmen, or Tartars, and they did all they could to determine their age.

But at that time, the study of Maya hieroglyphs and their calendar had scarcely begun. The true antiquity of the ancient centers of the Maya lowlands was only determined after the calendrical part of the Classic Maya inscriptions had been fully deciphered. The inscribed stone monuments of the lowland Maya sites have a system of dating called the Long Count, an exact, daily count reckoned from some mythical point in the distant past. Once this was understood, by the close of the nineteenth century, the problem naturally became one of correlating the Maya calendar with our own. Many specialists worked on this problem with differing results, but the most generally accepted correlation placed the period within which most of the Maya centers reached their full form as beginning slightly before CE 300 and ending around CE 900. The solving of the problem of the Maya Long Count has given archeologists the only absolute, day-by-day chronology that exists for Mesoamerica.

As ancient Mexican and Central American cultures were encountered and described, such as the Zapotec civilization of Oaxaca, or the Totonac ruins of El Tajín in the forested lowlands of north-central Veracruz, every effort was made to cross-date them with the Maya, so that the Maya time scale could be applied to their own chronology.

By the early decades of the twentieth century, it had become clear that the golden age of Mesoamerica was reached, not in the centuries just preceding the conquest, but long before that, in what is called the Classic. But what lay in back of the Classic? Such civilizations could not just have appeared out of thin air. And, with a few eccentric exceptions, no scholars by this time could believe in the old migration theories, mainly because the New World cultures were found to have been so different from those of the Old in form and in content; most importantly, the Mesoamerican food complex was built on plants like maize, the common bean, and the squash, none of which were known in the Old World before Columbus. All of these facts argued that the natives of the New World had been there for a very long time, and the civilizations of Mesoamerica must have been presaged by a lengthy period of development.

The true time span involved and the working out of the details of this gestation period had to wait for modern archeology, based upon the principle of stratigraphy. Simply stated, this means that archeological deposits usually occur in well-marked layers or strata and the deeper the layer in which an object is embedded, the older it is. It was taken over by British archeologists in the late nineteenth century from the geologists and, as in geology, the application of stratigraphic methods is often more complex than the principle suggests. The ideal stratigraphic situation is an undisturbed refuse heap in use over many generations: Careful excavations successively peeling layer from layer would show gradual changes in discarded cultural items from top to bottom, or from later to earlier.

For instance, a modern American city garbage dump might begin on bedrock with broken kerosene lamps and end up in the topmost stratum with fragments of fluorescent tubing. However, all kinds of disturbances of the stratigraphic record can happen at any time, such as the cutting down of storage pits, or the placing of burials, or the digging of trenches for building foundations. Only after considerable experience in archeological digging can one interpret such confusing situations.

It took a long time for such an obvious principle to be applied to New World archeology. In 1914, an American archeologist, Nels Nelson, tried it out on the refuse heaps or middens of the Pueblo Indians in the U.S. Southwest, giving a prehistoric past where there had been none at all. Nelson, like his predecessors in England, realized the value of pottery fragments or potsherds for establishing a sequence of cultural changes, for nothing changes so fast, is so breakable, or is so nearly universal as pottery.

Nelson, however, was “scooped” in the use of stratigraphy by the Mexican anthropologist Manuel Gamio, who four years before had made a deep cut in refuse layers in a site close to Mexico City. This simple excavation turned up no hidden treasure, no rich tombs, no buried temples, but something more important: the first stratified record of the peoples who had occupied the Valley of Mexico over a period of 1,500 years. At the top, obviously, were sherds and other artifacts of the Aztec civilization. Below this was refuse containing fragments of pottery of types known to come from the ruins of Teotihuacán.

And, finally, at very deep levels, were much simpler kinds of pottery and small handmade clay figurines of a culture that Gamio and others then called “Archaic” and which was thus proved to be even older than Teotihuacán. At one stroke, he had established a relative chronology for the Valley of Mexico: Archaic, followed by the Teotihuacán civilization, followed by the Aztec. In the next few decades, it was discovered that Toltec remains belonged between Teotihuacán and Aztec. In a way, then, the old chronicles of the Aztec had been correct.

Eventually, stratigraphic excavations were made over much of Mesoamerica, including the abandoned centers of the Classic Maya, and a remarkable picture emerged of the long, prehistoric sequence that went to make Mesoamerica. But all of this, with the exception of those ruins directly dated by the Maya Long Count calendar, was relative; that is, all that one could say was that culture A was older than culture B. which was, in turn, prior to culture C. But how much older?

The native “historical” chronicles were unfortunately hard to interpret, since they were based upon a kind of permutating chronology - a recurring cycle of fifty-two years - not tied to a consecutive time count, so that Teotihuacán, for instance, was hard to place in terms of our Christian calendar. In 1945, there were few archeologists who would have placed it earlier than CE 600; there were even fewer who would have put the beginning of the pre-Teotihuacán, Archaic cultures much earlier than the time of Christ.

What was clearly needed was some kind of absolute dating, independent of native calendars, which would furnish dates in terms of our own calendar. The discovery of the radiocarbon method was developed in the late 1940s by the American chemist, Willard Libby, for which he received the 1960 Nobel Prize. In the years since, radioactive dating has revolutionized the technique of archeology and the understanding of prehistory.

This remarkable “clock” is based upon the circumstance that a radioactive isotope of carbon, C14, is present in all living things. After the death of an organism, whether man, fish, or tree, this radioactive carbon decomposes at a known rate. After 5,568 years, one-half is gone; after another 5,568 years, one-half of this, and so on by halves until there is too little to measure in the elaborate Geiger counters used for this purpose. By measuring the activity of the C14 in a sample of charcoal from an ancient hearth, for instance, one can determine within a certain degree of statistical reliability the number of years ago the tree from which the firewood came was cut. Not only charcoal, but wood, bone, shell, cloth, and many other organic substances as much as 60,000 or 70,000 years old can be so dated by the C14 method.

The radiocarbon clock has revealed the full time depth of the American past. From this vantage point, it is clear that Mesoamerica, as with other great cultural hearths like the Near East, has advanced through a series of stages, or developmental levels, although not everybody exactly agrees as to what they were. A stage is by no means the same thing as a period, which refers only to a span of time. To clarify, everyone on this planet is now in the twenty-first century, which is a period. Some nations are in the Atomic Age, which is a stage; others have barely passed the Industrial Revolution, which is another stage; and many thousand natives of the New Guinea interior can be said to be in the Neolithic stage, which our ancestors left behind over 4,000 years ago. On a world scale, “progress” is thus a mosaic, with steps forward coming in scattered bits and pieces.

And so it was in Mesoamerica. A scheme of stages based upon many years of stratigraphic excavation and upon C14 dating is generally agreed upon, but not all regions within this vast area went through them at the same time. For instance, western Mexico probably never did achieve the Classic stage. For the present, though, five stages are generally accepted.

The original ancestors of the American Indians are now known to have crossed the barren, snow-swept land bridge that existed between Siberia and Alaska during the Ice Age, or Pleistocene epoch. When the first bands of wandering hunters came over, whether 12,000 or 40,000 years ago, is not known. But some time before 9000 BCE these primitive hunters had reached the North American continent; stone-tipped spears and darts were used to hunt the great herbivores - especially mammoths and mastodons - until the retreat of the northern glaciers after 8000 BCE.

Archaic is now used to describe the early stage of food-collecting eked out with primitive agriculture. This stage lasted in Mesoamerica from 7000 to about 1500 BCE.

The now-named Formative stage was what Gamio and other pioneer Mexican archeologists called the Archaic. Formative is used for a pre-Classic stage of intensified village life, with pottery, textiles, and all of the other “Neolithic” arts, lasting until CE 200 or 300.

The Classic, or so-called Golden Age of Mesoamerica, was the stage of great civilizations and great art, lasting from the end of the Formative until CE 900. By no accident, this also happened to be the span, or period, during which the Maya were carving their stone monuments with Long Count dates, confusing period with stage. It is now known, for instance, that Teotihuacán civilization, always included in the Classic, began before CE 200 and was pretty much finished by CE 600.

There is little doubt that by CE 900, most, or all, of the Classic civilizations were falling or had already fallen into ruins: Maya, Teotihuacán, Monte Albán, and so on. The Classic was succeeded by the Post-Classic, a new urban stage in which militarism became a way of life, and great conquest states, first the Toltec, then the Aztec, arose. The Post-Classic came to an end with the arrival of Cortés.

This, then, is the orderly scheme that has met with general acceptance, probably because it fits comfortably with a view of human cultural development as gradual and ordered: Progress is seen as a line of development gently sloping ever upward. For that reason, probably few archeologists were prepared for the disturbance which the discovery of the Olmec played with that neat curve: a Classic civilization right at the start of the Formative. To understand what this means, it is necessary to examine the food-producing “revolution” in Mesoamerica, which made the Olmec possible in the first place.