The Roman Missal () is the title of several missals used in the celebration of the Roman Rite. Along with other liturgical books of the Roman Rite, the Roman Missal contains the texts and rubrics for the celebration of the most common liturgy and Mass of the Catholic Church. History Before the Council of Trent (1570) Before the high Middle Ages, several books were used at Mass: a Sacramentary with the prayers, one or more books for the Scriptural readings, and one or more books for the antiphons and other chants. Gradually, manuscripts came into being that incorporated parts of more than one of these books, leading finally to versions that were complete in themselves. Such a book was referred to as a Missale Plenum (). In 1223 Saint Francis of Assisi instructed his friars to adopt the form that was in use at the Papal Court (Rule, chapter 3). They adapted this missal further to the needs of their largely itinerant apostolate. Pope Gregory IX considered, but did not put into effect, the idea of extending this missal, as revised by the Franciscans, to the whole Western Church; and in 1277 Pope Nicholas III ordered it to be accepted in all churches in the city of Rome. Its use spread throughout Europe, especially after the invention of the printing press; but the editors introduced variations of their own choosing, some of them substantial. Printing also favoured the spread of other liturgical texts of less certain orthodoxy. The Council of Trent determined that an end must be put to the resulting disparities. The first printed Missale Romanum (Roman Missal), containing the Ordo Missalis secundum consuetudinem Curiae Romanae (Order of the Missal in accordance with the custom of the Roman Curia), was produced in Milan in 1474. Almost a whole century passed before the appearance of an edition officially published by order of the Holy See. During that interval, the 1474 Milanese edition was followed by at least 14 other editions: 10 printed in Venice, 3 in Paris, 1 in Lyon. For lack of a controlling authority, these editions differ, sometimes considerably. Annotations in the hand of Cardinal Gugliemo Sirleto in a copy of the 1494 Venetian edition show that it was used for drawing up the 1570 official edition of Pope Pius V. In substance, this 1494 text is identical with that of the 1474 Milanese edition. From 1570 to