In the earliest service-books of the Roman and also of a few other churches, the Masses in honour of the martyrs were not classed by themselves apart, but were incorporated with the others, and not separated from the course of the ecclesiastical year, or, to use a modern expression, the _Proprium de Sanctis_ and the _Proprium de Tempore_ were still fused together. Only in the _Gelasianum_ are the _Natalitia sanctorum_ separated from the ecclesiastical year and collected together in the second volume. Still later were the catalogues of the saints formed into independent works, the so-called martyrologies. In the East these began to appear at an early date. In this a return was made to the older arrangement, except that now it was not the martyrs of the local churches alone which were taken into consideration, but those of the Church Universal. It is just this insertion of the saints’ days in the course of the Church’s year which proves that the names of the martyrs and the days of the commemoration were subject to the control of authority; that is to say, the compilations in question have all the weight attaching to public official documents and to reliable sources of information, and, for this reason, they may be used as material in historical works. Valuable information can be gained from a judicious employment of these compositions. The restriction of festivals to those commemorating saints of a specific locality disappeared only slowly, and at a late date in the West. It disappeared still later, and only to a limited extent, among the Easterns, who showed a tendency to fill up their calendars with other things rather than with the feasts of foreign martyrs and saints, as, for example, the commemorations of Councils, Old Testament personages, and even the four beasts of the Apocalypse were pressed into the service. In the West the entrance of the Franks and Anglo-Saxons into the Roman Church gave the first impulse to an extension of the martyrologies and calendars in the direction of universalism or universal Catholicity. Both these nations, having no Christian antiquity of their own, adopted along with the ritual of the Roman Church her calendar of saints as well. Soon, however, they added to this the names of their own particular saints, and so prepared the way for more universal ideas; while, on the contrary, the Roman Church did not include in her calendar the saints and martyrs of the Franks and Anglo-Saxons. Only at the revision of the service-books in the sixteenth century did she so far yield as to act in some degree upon the principle of Catholicity in this matter. The subsequent increase and development of the festivals of the saints in the Calendar of the Catholic Church had a disturbing effect upon the ecclesiastical year and daily office. Ordinary Sundays have lost their position and have given place to the commemoration of saints, and green vestments only rarely make their appearance.