The “Universal History” was concocted in a singular manner. In order to secure to it the greatest possible authority, he passed some years in a Tezcucan town, where he conferred daily with a number of respectable natives unacquainted with Castilian. He propounded to them queries, which they, after deliberation, answered in their usual method of writing, by hieroglyphical paintings. These he submitted to other natives, who had been educated under his own eye in the College of Santa Cruz; and the latter, after a consultation among themselves, gave a written version, in the Mexican tongue, of the hieroglyphics. This process he repeated in another place, in some part of Mexico, and subjected the whole to a still further revision by a third body in another quarter. He finally arranged the combined results into a regular history, in the form it now bears; composing it in the Mexican language, which he could both write and speak with great accuracy and elegance,—greater, indeed, than any Spaniard of the time.
The work presented a mass of curious information, that attracted much attention among his brethren. But they feared its influence in keeping alive in the natives a too vivid reminiscence of the very superstitions which it was the great object of the Christian clergy to eradicate. Sahagun had views more liberal than those of his order, whose blind zeal would willingly have annihilated every monument of art and human ingenuity which had not been produced under the influence of Christianity. They refused to allow him the necessary aid to transcribe his papers, which he had been so many years in preparing, under the pretext that the expense was too great for their order to incur. This occasioned a further delay of several years. What was worse, his provincial got possession of his manuscripts, which were soon scattered among the different religious houses in the country.