303

Year 303 (CCCIII) was a common year starting on Friday of the Julian calendar. It was known in the Roman Empire as the Year of the Consulship of Diocletian and Maximian (or, less frequently, year 1056 Ab urbe condita). The denomination 303 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

Events

Great Persecution: Emperor Diocletian launches the last and largest major persecution of Christians in the Empire. Caesar Galerius and Hierocles are said to have been the instigators. In a series of four edicts published from February 23, 303, to 304, the Christians are forbidden to worship in groups, are made to perform sacrifices, and must surrender sacred texts. Churches are destroyed, and the clergy are arrested en masse. The persecution lasts in some parts of the empire until 313, and thousands of Christians are killed. Those put to death include Agnes of Rome, a 12-year-old Christian girl who has refused marriage and consecrated her virginity to God. Hailed as a martyr, she will be honored as the patron saint of chastity, gardeners, rape victims and virgins.
September 25 – On a voyage preaching the gospel, Saint Fermin of Pamplona is beheaded in Amiens (Modern day France).
November 20 – The Augusti Diocletian and Maximian reunite in Rome to celebrate the 20th anniversary of Diocletian's accession, which is now treated as a joint anniversary for both emperors. A series of columns in the Roman Forum and a triumphal arch are dedicated to the emperors. The two emperors also agree on a plan of abdication.
Galerius wins his third victory over the Carpi and is perhaps joined on campaign by Diocletian. The Arch of Galerius is dedicated in Thessaloniki.<ref>Template:Cite book</ref>
Caesar Constantius I wins a victory over Germanic invaders in the battle of Vindonissa.