Feast Day of St. Januarius!

Januarius (/ˌdʒæn.juˈɛəriəs/ JAN-yoo-AIR-ee-əs; Latin: Ianuarius; Neapolitan and Italian: Gennaro), also known as Januarius I of Benevento, was Bishop of Benevento and is a martyr and saint of the Catholic Church and the Eastern Orthodox Church. While no contemporary sources on his life are preserved, later sources and legends claim that he died during the Great Persecution, which ended with Diocletian's retirement in 305.
Januarius is the patron saint of Naples, where the faithful gather three times a year in Naples Cathedral to witness the liquefaction of what is claimed to be a sample of his blood kept in a sealed glass ampoule.
Little is known of the life of Januarius, and what follows is mostly derived from later Christian sources, such as the Acta Bononensia (BHL 4132, not earlier than 6th century) and the Acta Vaticana (BHL 4115, 9th century), and from later folk traditions.
According to various hagiographies, Januarius was born in Benevento to a rich patrician family that traced its descent to the Caudini tribe of the Samnites. At a young age of 15, he became local priest of his parish in Benevento, which at the time was relatively pagan. When Januarius was 20, he became Bishop of Naples and befriended Juliana of Nicomedia and Saint Sossius whom he met during his priestly studies. During the 1+1⁄2-year-long persecution of Christians by Emperor Diocletian, he hid his fellow Christians and prevented them from being caught. Unfortunately, while visiting Sossius in jail, he too was arrested. He and his colleagues were condemned to be thrown to wild bears in the Flavian Amphitheater at Pozzuoli, but the sentence was changed due to fear of public disturbances, and they were instead beheaded at the Solfatara crater near Pozzuoli. Other legends state either that the wild beasts refused to eat them, or that he was thrown into a furnace but came out unscathed
The earliest extant mention of him is contained in a 432 letter by Uranius, bishop of Nola, on the death of his mentor Saint Paulinus of Nola, where it is stated that the ghosts of Januarius and Saint Martin appeared to Paulinus three days before the latter's death in 431. About Januarius, the account says only that he was "bishop as well as martyr, an illustrious member of the Neapolitan church". The Acta Bononensia says that "At Pozzuoli in Campania [is honored the memory] of the holy martyrs Januarius, Bishop of Beneventum, Festus his deacon, and Desiderius lector, together with Sossius deacon of the church of Misenum, Proculus, deacon of Pozzuoli, Eutyches, and Acutius, who after chains and imprisonment were beheaded under the emperor Diocletian".
The Feast of St Januarius or San Gennaro is celebrated on 19 September in the calendar of the Catholic Church. In the Eastern Church, it is celebrated on 21 April. The city of Naples has more than fifty official patron saints, although its principal patron is Saint Januarius.
In the United States, the "Feast of San Gennaro" is also a highlight of the year for New York's Little Italy, with the saint's polychrome statue carried through the middle of a street fair stretching for blocks.
According to an early hagiography, Januarius's relics were transferred by order of Saint Severus, Bishop of Naples, to the Neapolitan catacombs "outside the walls" (extra moenia). In the early ninth century the body was moved to Beneventum by Sico, prince of Benevento, with the head remaining in Naples. Subsequently, during the turmoil at the time of Frederick Barbarossa, his body was moved again, this time to the Territorial Abbey of Montevergine where it was rediscovered in 1480.
At the instigation of Cardinal Oliviero Carafa, his body was finally transferred in 1497 to Naples, where he is the city's patron saint. Carafa commissioned a richly decorated crypt, the Succorpo, beneath the cathedral to house the reunited body and head properly. The Succorpo was finished in 1506 and is considered one of the prominent monuments of the High Renaissance in the city.
Saint Januarius is famous for the miracle of the annual liquefaction of his blood, which, according to legend, was saved by a woman called Eusebia just after the saint's death. A chronicle of Naples written in 1382 describes the cult of Saint Januarius in detail, but mentions neither the relic nor the miracle. The first certain date is 1389, when it was found to have melted. Then, over the following two and a half centuries official reports began to appear declaring that the blood spontaneously melted, at first once a year, then twice, and finally three times a year. While the report of the very first incidence of liquefaction did not make any explicit reference to the skull of the saint, soon afterwards assertions began to appear that this relic was activating the melting process, as if the blood, recognizing a part of the body to which it belonged, "were impatient while waiting for its resurrection". This explanation was definitively abandoned only in the eighteenth century.
Thousands of people assemble to witness this event in Naples Cathedral three times a year: on September 19 (Saint Januarius's Day, commemorating his martyrdom), on December 16 (celebrating his patronage of Naples and its archdiocese), and on the Saturday before the first Sunday of May (commemorating the reunification of his relics).
The blood is also said to spontaneously liquefy at certain other times, such as papal visits. It supposedly liquefied in the presence of Pope Pius IX in 1848, but not that of John Paul II in 1979 or Benedict XVI in 2007. On March 21, 2015, Pope Francis venerated the dried blood during a visit to Naples Cathedral, saying the Lord's Prayer over it and kissing it. Archbishop Sepe then declared that "The blood has half liquefied, which shows that Saint Januarius loves our pope and Naples."