These plays, constituting a distinct and peculiar class, received a name of their own, and were at first called autos (from the Latin actus, applied to any particularly solemn act, as autos-da-fe), and later more specifically autos sacramentales.
We infer from occasional notices that these religious dramas were performed without interruption during the XIVth and XVth centuries. What their character was during this period we do not know, as we possess none earlier than the beginning of the XVIth century.
From this last-named date notices of the secular drama begin to multiply, and we may form some idea of the early autos sacramentales from the productions of Juan de la Enzina and Gil Vicente.
The former wrote a number of religious dialogues or plays, which he named eclogues, probably because the majority of the characters were shepherds.
One of these eclogues is on the Nativity, another on the Passion and Death of our Redeemer.
The word auto, as we have stated, was applied to any solemn act, and did not at first refer exclusively to the Corpus Christi dramas, so we find among the works of Gil Vicente an auto for Christmas, and one on the subject of S. Martin, which, although having nothing to do with the mystery of the Eucharist, was performed during the celebration of Corpus Christi in 1504, in the vestibule of the Church of Las Caldas in Lisbon.
These sacred plays were undoubtedly at first represented only in the churches by the ecclesiastics; they were not allowed to be performed in villages (where they could not be supervised by the higher clergy), or for the sake of money.
The abuses in their performance, or perhaps the large number of spectators, afterwards led to their representation in the open air.
The stage (as in the beginning of the classical drama) was a wagon, on which the scenery was arranged; when the autos became more elaborate, three of these wagons or carros were united.
We may see what these primitive stages were like in Don Quixote (part ii. chap. 11), the hero of which encountered upon the highway one of these perambulating theatres: