dead was likened to Osiris's rebirth, as well as to Ra's journey through the underworld in Egyptian myth, possibly implying that Isis brought the initiate back from death as she did her husband. Festivals Roman calendars listed the two most important festivals of Isis as early as the first century CE. The first festival was the Navigium Isidis in March, which celebrated Isis's influence over the sea and served as a prayer for the safety of seafarers and, eventually, of the Roman people and their leaders. It consisted of an elaborate procession, including Isiac priests and devotees with a wide variety of costumes and sacred emblems, carrying a model ship from the local Isis temple to the sea or to a nearby river. The other was the Isia in late October and early November. Like its Egyptian forerunner, the Khoiak festival, the Isia included a ritual reenactment of Isis's search for Osiris, followed by jubilation when the god's body was found. Several more minor festivals were dedicated to Isis, including the Pelusia in late March that may have celebrated the birth of Harpocrates, and the Lychnapsia, or lamp-lit festival, that celebrated Isis's own birth on August 12. Festivals of Isis and other polytheistic deities were celebrated throughout the fourth century CE, despite the growth of Christianity in that era and the persecution of pagans that intensified toward the end of the century. The Isia was celebrated at least as late as 417 CE, and the Navigium Isidis lasted well into the sixth century. Increasingly, the religious meaning of all Roman festivals was forgotten or ignored even as the customs continued. In some cases, these customs became part of the combined classical and Christian culture of the Early Middle Ages. Possible influence on Christianity A contentious question about Isis is whether her cult influenced Christianity. Some Isiac customs may have been among the pagan religious practices that were incorporated into Christian traditions as the Roman Empire was Christianized. Andreas Alföldi, for instance, argued in the 1930s that the medieval Carnival festival, in which a model boat was carried, developed from the Navigium Isidis. Much attention focuses on whether traits of Christianity were borrowed from pagan mystery cults, including that of Isis. The more devoted members of Isis's cult made a personal commitment to a deity they regarded as superior to others, as Christians did. Both Christianity and the Isis cult had