The authorities on which our knowledge of aboriginal history rests are native traditions orally handed down from generation to generation, the Aztec picture-writings that still exist, the writings of the Spanish authors who came in contact with the natives in the period immediately following the Conquest, and also of converted native writers who wrote in Spanish, or at least by the aid of European letters. In connection with these positive authorities the actual condition, institutions, and beliefs of the natives at the Conquest, together with the material monuments of antiquity, all described in the preceding volumes, constitute an important illustrative, corrective, or confirmatory source of information.
Oral tradition, in connection with linguistic affinities, is our only authority in the case of the wild tribes, and also plays a prominent part in the annals of the civilized nations. In estimating its historical value, not only the intrinsic value of the tradition itself, but the authenticity of the version presented to us must be taken into consideration; the latter consideration is, however, closely connected with that of the early writers and their reliability as authorities on aboriginal history. No tribe is altogether without traditions of the past, many – probably most – of which were founded on actual occurrences, while a few are wholly imaginary. Yet, whatever their origin, all are, if unsupported by written records, practically of little or no value. Every trace of the circumstances that gave rise to a tradition is soon lost, although the tradition itself in curiously modified forms is long preserved. Natural convulsions, like floods and earthquakes, famines, wars, tribal migrations, naturally leave an impression on the savage mind which is not easily effaced, but the fable in which the record is embodied may have assumed a form so changed and childish that we pass over it to-day as having no historical value, seeking information only in an apparently more consistent tale, which may have originated at a recent date from some very trivial circumstance. Examples are not wanting of very important events in the comparatively modern history of Indian tribes, the record of which has not apparently been preserved in song or story, or the memory of which at least has become entirely obliterated in little more than a hundred years. Oral tradition has no chronology that is not purely imaginary; "many moons ago," "our fathers did thus and so," may refer to antediluvian times or to the exploits of the narrator's grandfather. Among the American savages there was not even a pride in the pedigree of families or horses to induce care in this respect, as among the Asiatic hordes of patriarchal times. But the traditions of savages, valueless by themselves for a time more remote than one or two generations, begin to assume importance when the events narrated have been otherwise ascertained by the records of some contemporary nation, throwing indirectly much light on history which they were powerless to reveal. Three traditions are especially prevalent in some form in nearly every section of America; – that of a deluge, of an aboriginal migration, and of giants that dwelt upon the earth at some time in the remote past. These may be taken as examples and interpreted as follows, the respective interpretations being arranged in the order of their probability.
The tradition of a flood would naturally arise, 1st, from the destruction of a tribe or part of a tribe by the sudden rising of a river or mountain stream – that is from a modern event such as has occurred at some time in the history of nearly every people, and which a hundred years and a fertile imagination would readily have converted into a universal inundation. 2d. From the finding of sea-shells and other marine relics inland, and even on high mountains, suggesting to the natives' untutored mind what it proves to later scientific research – the fact that water once covered all. 3d. From the actual submersion of some portions of the continent by the action of volcano or earthquake, an event that geology shows not to be improbable, and which would be well calculated to leave a lasting impression on the minds of savages. 4th. From the deluge of the scriptural tradition, the only one of the many similar events that may have occurred which makes any claims to have been historically recorded. The accompanying particulars would be naturally invented. Some must have escaped, and an ark or a high mountain are the natural means.
A traditional migration from north, south, east, or west may point to the local journeying of a family or tribe, either in search of better hunting-grounds, or as a result of adverse fortune in war; in a few cases a general migration of many tribes constituting a great nation may be referred to; and finally, it is not quite impossible that a faint memory of an Old World origin may have survived through hundreds of generations.
So with the giant tradition, resulting, 1st, from the memory of a fierce, numerous, powerful, and successful enemy, possibly of large physique. No tribe so valiant that it has not met with reverses, and the attributing of gigantic strength and supernatural powers to the successful foe, removes among the descendants the sting of their ancestors' defeat. 2d. From the discovery of immense fossil bones of mastodons and other extinct species. It is not strange that such were deemed human remains by the natives when the Spaniards in later times have honestly believed them to be the bones of an extinct gigantic race. 3d. From the existence of grand ruins in many parts of the country, far beyond the constructive powers of the savage, and therefore in his eyes the work of giants – as they were intellectually, in comparison with their degenerate descendants. 4th. From an actual traditional remembrance of those who built the ruined cities, and intercourse with comparatively civilized tribes. 5th. From the existence in primitive times of a race of giants.
Numerous additional sources for each of these traditions might doubtless be suggested; but those given suffice for illustration, and, as I have remarked, they are arranged in each case in what would seem the natural order of probability. The near and natural should always be preferred to the remote and supernatural; and the fables mentioned should be referred to Noah's deluge, Asiatic origin, and the existence of a gigantic race, only when the previous suppositions are proved by extraneous evidence to be untenable. The early writers on aboriginal America, using their reason only when it did not conflict with their faith, reversed the order of probability, and thus greatly impaired the usefulness of their contributions to history. The supposition of a purely imaginary origin, common to aboriginal legend and modern romance, should of course be added to each of the preceding lists, and generally placed before the last supposition given.
Passing from the wild tribes to the civilized nations of Mexico and Central America, we find tradition, or what is generally regarded as such, much more complete and extensive in its scope, less childish in detail, and with a more clearly defined dividing line between history and mythology. Theoretically we might expect a higher grade of tradition among a partially civilized people; but on the other hand, what need had the Nahuas or Mayas of oral tradition when they had the art of recording events? In fact, our knowledge of Aztec and Maya history is not in any proper sense traditional, although commonly spoken of as such by the writers. Previous to the practice of the hieroglyphic art – the date of whose invention or introduction is unknown, but must probably be placed long before the Christian era – oral tradition was doubtless the only guide to the past; but the traditions were recorded as soon as the system of picture-writing was sufficiently perfected to suggest if not to clearly express their import. After picture-writing came into general use, it is difficult to imagine that any historical events should have been handed down by tradition alone. Still in one sense the popular knowledge of the past among the Mexicans may be called traditional, inasmuch as the written records of the nation were not in the hands of the people, but were kept by a class of the priesthood, and may be supposed to have been read by comparatively few. The contents of the records, however, except perhaps some religious mysteries which the priests alone comprehended, were tolerably well known to the educated classes; and when the records were destroyed by Spanish fanaticism, this general knowledge became the chief source whence, through the 'talk of the old men,' the earlier writers drew their information. It is in this light that we must understand the statement of many able writers, that the greater part of our knowledge of early American history is traditional, since this knowledge was not obtained by an actual examination of the records by the Spaniards, but orally from the people, the upper classes of whom had themselves read the pictured annals, while the masses were somewhat familiar through popular chants and plays with their contents. The value of history faithfully taken from such a source cannot be doubted, but its vagueness and conflicting statements respecting dates and details may be best appreciated by questioning intelligent men in the light of nineteenth century civilization