Accepting this as established, the possibility of fixing the European identity of Quetzatcoatl presents itself as a curious but obviously difficult question. To begin with, the era of Quetzatcoatl is not known with any precision. It has a possible range of some six and a half centuries from before the beginning of the fourth century to the middle of the tenth century; that is, from about A. D. 400 to A. D. 1050, which is the longest time assigned to Toltec domination in Mexico. The era of Quetzatcoatl may, however, be safely confined to narrower limits. The Toltecs must have been well settled in the country before Quetzatcoatl appeared among them, and he must have left them some considerable time before their migration from Mexico. The references to Quetzatcoatl's visits to the Toltec cities prove the former, and the time which would have been required to arrange for and complete the great pyramid built at Cholula in honor of the departed Quetzatcoatl proves the latter. From a century to two centuries may be allowed at each end of the period from a. d. 400 to a. d. 1050, and it may be assumed with some degree of probability that Quetzatcoatl's visit to Mexico took place some time between (say) a. d. 500 and A. D. 900.
If attention is directed to the condition of Europe during that time, it will be found that the period from about a. d. 500 to a. d. 800 was one of great missionary activity. Before the former date the Church was doing little more than feeling its way and developing its strength in the basin of the Mediterranean, and making extensions in settled states. After the latter date the incursions and devastations of the northern barbarians paralyzed European missionary efforts. But from the beginning of the fifth to the beginning of the eighth century there was no limit to missionary enterprise, and, if ever a Christian missionary had appeared in Mexico, all the probabilities favor the theory that he must have gone there within those centuries. The era of Quetzatcoatl may therefore be narrowed to those three hundred years, and the task of tracing his identity thus simplified to some slight extent.
It may now be asked, Is it reasonable to expect that there are, or ever were, any European records of the period from a. d. 500 to A. D. 800 referring to any missionary who might have been Quetzatcoatl? It is a long time since Quetzatcoatl, whoever he was, sailed from the shores of Europe to carry the truths of Christianty into the unknown regions beyond the Atlantic, but the literary records of his assumed period are numerous and minute, and might possibly have embraced some notice of his undertaking. It seems unlikely that his enterprise would have escaped attention altogether, especially from the ecclesiastical chroniclers, who were not given to ignoring the good works of their fellow-religionists. Moreover, the mission of Quetzatcoatl was not one
