Today’s solemnity has its roots in the earliest days of the Church. Even in the New Testament times, martyrs were honored by the community of believers, beginning with the deacon Saint Stephen, the first martyr. As the first century of the Church unfolded, others began to suffer persecution and death at the hands of Roman emperors, and the Church honored their deaths. In 64, Emperor Nero was the first to organize a persecution of Christians in Rome, taking the lives of Saints Peter and Paul, and many others. After this first persecution in Rome, other Roman emperors systematized various persecutions throughout the entire empire. The worst persecution took place under Emperor Diocletian from 303–311. During that persecution, churches and sacred texts were destroyed; Christians lost their property, legal rights, and lives; and those who were not killed were imprisoned and tortured. Some estimate that during the Diocletian persecutions, there were as many as 3,500 martyrs. Although there is no way to confirm the exact number, there were many.
In the fourth century, after Christianity was legalized in 313 by Emperor Constantine I, who became a Christian himself and began building churches and monuments to the martyrs, public devotion to the martyrs began to flourish. Their graves became churches and places of pilgrimage and prayer. On May 13, 609, Pope Boniface IV transformed the Pantheon in Rome, a former pagan temple, into a church dedicated to the Blessed Virgin Mary and all martyrs. The annual celebration of its dedication also honored the Blessed Virgin Mary and all martyrs. On November 1, 731, Pope Gregory III dedicated an oratory within Saint Peter’s Basilica to “all saints” that included the Apostles, martyrs, confessors, and all holy men and women throughout the world. This broadened the commemoration of the saints beyond the martyrs to all who lived saintly lives. In 844, Pope Gregory IV extended the November 1 celebration to the entire Church. In 1484, Pope Sixtus IV made November 1 a holy day of obligation for the entire Church.
