Diocletian, nicknamed Jovius, was Roman emperor from 284 until his abdication in 305. He was born Diocles to a family of low status in the Roman province of Dalmatia. Diocles rose through the ranks of the military early in his career, eventually becoming a cavalry commander for the army of Emperor Carus. After the deaths of Carus and his son Numerian on a campaign in Persia, Diocles was proclaimed emperor by the troops, taking the name Diocletianus. The title was also claimed by Carus's surviving son, Carinus, but Diocletian defeated him in the Battle of the Margus.
Gregory the Illuminator was the founder and first official head of the Armenian Apostolic Church. He converted Armenia from Zoroastrianism to Christianity in the early fourth century, making Armenia the first state to adopt Christianity as its official religion. He is venerated as a saint in the Armenian Apostolic Church and in some other churches.
The 4th century was the time period from AD 301 to AD 400 (CD) in accordance with the Julian calendar. In the West, the early part of the century was shaped by Constantine the Great, who became the first Roman emperor to adopt Christianity. Gaining sole reign of the empire, he is also noted for re-establishing a single imperial capital, choosing the site of ancient Byzantium in 330 to build the city soon called Nova Roma ; it was later renamed Constantinople in his honor.
The 300s decade ran from January 1, 300, to December 31, 309.
The 310s decade ran from January 1, 310, to December 31, 319.
The 240s decade ran from January 1, 240, to December 31, 249.
The 290s decade ran from January 1, 290, to December 31, 299.
The 280's decade ran from January 1, 280, to December 31, 289.
Year 300 (CCC) was a leap year starting on Monday of the Julian calendar. At the time, it was known as the Year of the Consulship of Constantius and Valerius. The denomination 300 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.
Year 298 (CCXCVIII) was a common year starting on Saturday of the Julian calendar. At the time, it was known as the Year of the Consulship of Faustus and Gallus. The denomination 298 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.
Year 247 (CCXLVII) was a common year starting on Friday of the Julian calendar. At the time, it was known as the Year of the Consulship of Philippus and Severus. The denomination 247 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.
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. 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.
Year 306 (CCCVI) was a common year starting on Tuesday of the Julian calendar. At the time, it was known as the Year of the Consulship of Constantius and Valerius. The denomination 306 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.
Year 337 (CCCXXXVII) was a common year starting on Saturday of the Julian calendar. At the time, it was known as the Year of the Consulship of Felicianus and Titianus. The denomination 337 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.
Sima Lun, courtesy name Ziyi (子彛), was titled the Prince of Zhao and the usurper of the Jin Dynasty from February 3 to May 31, 301. He is usually not counted in the list of Jin emperors due to his brief reign, and was often mentioned by historians as an usurper. He was the third of the eight princes commonly associated with the War of the Eight Princes.
A calendar era is the period of time elapsed since one epoch of a calendar and, if it exists, before the next one. For example, it is the year 2024 as per the Gregorian calendar, which numbers its years in the Western Christian era.
Zhang Hua, courtesy name Maoxian, was a Chinese poet and politician of the Western Jin dynasty and the preceding state of Cao Wei. An accomplished poet, Zhang also authored the Bowuzhi, a compendium of entries about natural wonders and supernatural phenomena. His political career reached its zenith from 291 to 300, when he served as a leading minister during the de facto regency of Empress Jia Nanfeng. Zhang was considered an effective minister and, in conjunction with his colleague Pei Wei, helped ensure a period of relative stability within the Jin court. As the court fell into factional disputes from 299 to 300, Zhang rebuffed the rebellious overtures of the imperial relative Sima Lun and was executed when the latter seized power from the empress.
Sima Jiong (司馬冏), courtesy name Jingzhi (景治), formally Prince Wumin of Qi (齊武閔王), was an imperial prince of the Jin dynasty of China. He briefly served as Emperor Hui's regent after overthrowing the usurper Sima Lun in May 301. He was the fourth of the eight princes commonly associated with the War of the Eight Princes.
As of 2011, most Armenians in Armenia are Christians (97%) and are members of the Armenian Apostolic Church, which is one of the oldest Christian churches. It was founded in the 1st century AD, and in 301 AD became the first branch of Christianity to become a state religion.
Christianity in the 4th century was dominated in its early stage by Constantine the Great and the First Council of Nicaea of 325, which was the beginning of the period of the First seven Ecumenical Councils (325–787), and in its late stage by the Edict of Thessalonica of 380, which made Nicene Christianity the state church of the Roman Empire.
