Letters abound in the records of early Spanish America. Or at least, public correspondence does. Members of all of the different official hierarchies were constantly writing to higher authority, and especially to the Spanish crown, petitioning, proposing, polemicizing. All corporations and interest groups did the same, and so did individuals when aggrieved or desirous of favors. The strident texts produced by this activity were long the main corpus with which historians of the Spanish Indies worked, first taking them at face value, then learning to appreciate their conventions, their propagandistic nature, their systematic distortions when compared with other types of evidence. New evidence emerged in many forms, from tax lists to notarial records, but rarely indeed, until recently, in the true counterpart of official correspondence, that is, private correspondence.

Were there no private letters? Scholars were long inclined to think so, and they even incorporated the supposed lack of intimate written expression into theories of the Spanish character. But in fact there were, and today's scarcity is only the result of the vulnerability of private correspondence to loss. From the examples that have been coming to light one can deduce that letter-writing among private individuals was a well-established custom in both Spain and the Indies (as the Spaniards persisted in calling America). Correspondents acknowledge previous letters, complain of lack of mail, speak of the cheapness of paper and ink, and in other ways betray that it was customary to write letters to absent relatives and friends. The genre was mature, with a complete set of salutations and courtesy endings, and certain conventions of vocabulary and structure, such as for example the frequent use of the word razon ('right,’ ‘reason’) somewhere in the beginning sentences.

Letters must have originated in all areas and gone in all directions, but in general only those which found a place in some official repository have been preserved. Most to appear so far were written from the Indies to relatives and associates in Spain. Of letters directed from Spain to the Indies we know little more than what we can deduce from the replies of the settlers, namely that they contained frequent appeals for money.