Religion & Belief in the 3rd century

80 sourced entries, 200 CE to 299 CE, oldest first. Also see Religion & Belief across every century or everything else in the 3rd century.

• 200Brahmanism evolves into Hinduism (approximate date).source
• 202An edict bans conversions to Christianity and all Christian propaganda.source
• 203Origen replaces Clement as the head of the Christian school in Alexandria.source
• 208December 10 – Cao Cao writes Duǎn Ge Xíng.source
• 209Publius Septimius Geta receives the titles of Imperator and Augustus from his father, Emperor Septimius Severus.source
• 211January – Warlord Cao Cao writes Ràng Xiàn Zì Míng Běn Zhì Lìng (讓縣自明本志令)source
• 211Marcus I is succeeded by Philadelphus, as Patriarch of Constantinople.source
• 217December 20 – The papacy of Zephyrinus ends. Callixtus I is elected as the sixteenth pope, but is opposed by the theologian Hippolytus who accuses him of laxity and of being a Modalist, one who denies any distinction between the three persons of the Trinity.source
• 217Hippolytus begins his "pontificate" as antipope and sets up a breakaway church for Christian followers.source
• 219Emperor Elagabalus, age 15, is initiated into the worship of the Phrygian gods Cybele and Attis.source
• 220The Wei dynasty gives official recognition to Taoism as its religious sect, and the sect's celestial masters reciprocate, by giving spiritual approbation to the Wei as successors to the Han. By the end of the century, most powerful families in northern China have subscribed to Daoist principles.source
• 222October 14 – Pope Callixtus I is killed by a mob in Rome's Trastevere after a 5-year reign in which he has stabilized the Saturday fast three times per year, with no food, oil, or wine to be consumed on those days. Callixtus is succeeded by Cardinal Urban I.source
• 230July 21 – Pope Pontian succeeds Pope Urban I, as the 18th pope of Rome.source
• 230Seventy bishops hold the council of the Christian Church of Africa.source
• 230Patriarch Castinus succeeds Ciriacus I as patriarch Constantinople.source
• 232Origen founds a school of Christian theology in Palestine.source
• 232Pope Heraclas of Alexandria is the first Bishop of Alexandria to use the appellation of "Pope".source
• 232Relics of St. Thomas are brought to Edessa from India.source
• 235September 28 – Pope Pontian resigns, the first to abdicate, because he and Hippolytus, church leader of Rome, are exiled to the mines of Sardinia. Emperor Maximinus persecutes the Christians.source
• 235November 21 – Anterus succeeds Pontian as the nineteenth pope of Rome.source
• 236January 10 – Pope Fabian succeeds Pope Anterus as the twentieth pope.source
• 236Fabian separates Rome into seven deaconships.source
• 237Saint Babylas becomes Patriarch of Antioch.source
• 237Patriarch Eugenius I succeeds Patriarch Castinus as Patriarch of Constantinople.source
• 238c. May – The Senate outlaws Maximinus for his bloodthirsty proscriptions in Ancient Rome and nominates two of its members, Pupienus and Balbinus, to the throne.source
• 239Origen publishes the Old Testament in five languages (approximate date).source
• 240Mani, a young mystic of Ctesiphon, proclaims himself a prophet at the court of Ardashir I. He preaches his doctrine, Manichaeism, throughout the Sassanid Empire.source
• 241The Dura-Europos church is converted from a house in Syria (approximate date).source
• 242Patriarch Titus succeeds Eugenius I as Patriarch of Constantinople (until 272).source
• 244Philip the Arab is recognized by the Roman Senate as the new Roman Emperor with the honorific Augustus. He nominates his son Philippus, age 6, with the title of Caesar and makes him heir to the throne; gives his brother Priscus supreme power (rector Orientis) in the Eastern provinces; and begins construction of the city of Shahba (Syria) in the province of his birth.source
• 246The first of two Councils of Arabia in the Roman Christian Church is held in Bostra, Arabia Petraea.source
• 247The last of the two Councils of Arabia in the Roman Christian Church is held in Bostra, Arabia Petraea.source
• 248Origen writes an eight-volume work, criticizing the pagan writer Celsus.source
• 249Decian persecution: Decius begins persecuting Christians, and others refusing to sacrifice publicly to the Roman gods for the well-being of the emperor.source
• 249Cyprian, Christian writer of Berber descent, becomes bishop of Carthage.source
• 250January 3 – Decian persecution of Christians is initiated when Emperor Decius orders everyone in the Roman Empire (except Jews) to perform a sacrifice to the gods of religion in ancient Rome. On January 20, Pope Fabian becomes one of the first martyrs of this persecution.source
• 250Possible date – Denis, a bishop of Paris, is martyred by beheading.source
• 251March – Pope Cornelius succeeds Pope Fabian as the 21st pope.source
• 251May – The first Synod of Carthage, a pre-ecumenical council, is held under the presidency of Saint Cyprian.source
• 252Pope Cornelius is exiled to Centumcellae, by Emperor Trebonianus Gallus.source
• 253June 25 – Pope Lucius I succeeds Pope Cornelius as the 22nd pope.source
• 253Pope Cornelius is sent into exile.source
• 254May 12 – Pope Stephen I succeeds Pope Lucius I.source
• 256February 28 – Papyrus Oxyrhynchus 3035, a warrant for the arrest of a Christian, is written.source
• 256Emperor Valerian persecutes Christians.source
• 256Pope Stephen I threatens to excommunicate Cyprian, bishop of Carthage, and other bishops in Africa and Asia Minor, unless they stop rebaptizing heretics. Cyprian attacks the Pope in a treatise that gains support from the Council of Carthage. He sends envoys to Rome, raising the specter of a schism between the Roman and Carthaginian Churches.source
• 257August 30 – Pope Sixtus II succeeds Pope Stephen I as the 24th pope.source
• 257Valerian's persecution of Christians begins: his edict orders bishops and priests to sacrifice according to the pagan rituals, and prohibits Christians, under penalty of death, from meeting at the tombs of their deceased.source
• 257The Goths separate into the Ostrogoths and the Visigoths.source
• 258Cyprian, bishop of Carthage, is martyred (decapitation).source
• 258A second Imperial edict prohibits Christianity in the Roman Empire. This edict divides Christians into four categories: priests, who are to be put to death; senators and equestrians, who are to be stripped of their positions and their property confiscated; nuns, who are to be exiled; and imperial civil servants, who are condemned to forced labour.source
• 258Pope Sixtus II, bishop of Rome, is martyred.source
• 259Pope Dionysius is elected as the pope.source
• 260Pope Dionysius convenes a synod at Rome to demand an explanation from bishop Dionysius of Alexandria, who has been charged with separating the members of the Trinity as three distinct deities.source
• 260Paul of Samosata becomes Patriarch of Antioch.source
• 261Gallienus repeals the edict of 258, which led to the persecution of the Christians.source
• 268Claudius II asks the Senate to spare the lives of Gallienus's family and political supporters. Emperor Gallienus is deified and buried in a family tomb on the Appian Way.source
• 269January 5 – Pope Felix I succeeds Dionysius as the 26th pope of Rome.source
• 269Paul of Samosata is deposed as Patriarch of Antioch (though he is not removed until 272).source
• 270Anthony the Great, a Christian saint from Egypt, regarded as "Father of All Monks", enters the wilderness to become ascetic.source
• 272Dometius succeeds Titus as Patriarch of Constantinople.source
• 272Paul of Samosata is deposed as Patriarch of Antioch.source
• 272Aurelian supports the bishops of Italy in deposing the bishop of Antioch, Paul of Samosata, who had been a supporter of Zenobia. This is the first recorded instance of an imperial intervention in an ecclesiastical dispute.source
• 272Saint Denis, first Bishop of Paris, and two of his disciples are beheaded on the road to the Temple of Mercury that stands atop a hill outside of the city. The hill will later be called Montmartre (Mountain of Martyrs) in Lutetia (modern Paris).source
• 274December 25 – Aurelian has the Temple of the Sun dedicated to Sol Invictus, on the third day after the solstice and day of rebirth of the sun. This religion, which is in essence monotheistic, becomes the state religion of Rome.source
• 275January 4 – Eutychian succeeds Felix I as the 27th pope of Rome.source
• 275November/December – Marcus Claudius Tacitus is proclaimed Emperor by the imperial field army (other sources give him as proclaimed September 25 by the Senate). His half brother Marcus Annius Florianus becomes praetorian prefect.source
• 282The Patriarch Theonas of Alexandria becomes one of the first bishops to use the title Pope.source
• 282Carus appoints his sons Carinus and Numerian as Caesar.source
• 283December 17 – Pope Caius succeeds Eutychian as the 28th pope of Rome.source
• 284November 17 – Diocletian becomes emperor of Romesource
• 284Rufinus succeeds Dometius as Bishop of Byzantium.source
• 284King of Kings Bahram II installs Mirian III, of the House of Mihran, on the throne of the Kingdom of Iberia. Mirian would rule the kingdom until his death in c. 361.source
• 285July 21 or July 25 – Diocletian appoints his fellow-officer Maximian to the office of caesar, or junior co-emperor.source
• 292The oldest known Mayan stele is erected at the capital Tikal (modern Guatemala).source
• 293March 1 – Emperors Diocletian and Maximian appoint Constantius I and Galerius as Caesars. This is considered the beginning of the Tetrarchy, known as the Quattuor Principes Mundi ("Four Rulers of the World"). (Some sources and scholars date Galerius' elevation to May 21.)source
• 293Probus succeeds Rufinus, as Bishop of Byzantium.source
• 295Petra rejoins the province of Palestine, and is converted to Christianity by the Syrian monk Barsauma.source
• 295Diocletian, perhaps through Galerius, issues an edict against incest.source
• 299Returning to Rome in triumph, Maximian commissions the Baths of Diocletian in honour of his 'brother' Diocletian.source