Year 317 (CCCXVII) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Gallicanus and Bassus (or, less frequently, year 1070 Ab urbe condita). The denomination 317 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.
|Ab urbe condita||1070|
|Balinese saka calendar||238–239|
|Chinese calendar||丙子年 (Fire Rat)|
3013 or 2953
— to —
丁丑年 (Fire Ox)
3014 or 2954
|- Vikram Samvat||373–374|
|- Shaka Samvat||238–239|
|- Kali Yuga||3417–3418|
|Iranian calendar||305 BP – 304 BP|
|Islamic calendar||314 BH – 313 BH|
|Minguo calendar||1595 before ROC|
|Seleucid era||628/629 AG|
|Thai solar calendar||859–860|
443 or 62 or −710
— to —
444 or 63 or −709
- March 1 – Emperor Constantine the Great and co-emperor Licinius elevate their sons Crispus, Constantine II (being still a baby) and Licinius II to Caesars. After this arrangement Constantine rules the dioceses Pannonia and Macedonia, and establishes his residence at Sirmium, from where he prepares a campaign against the Goths and Sarmatians.
- Licinius recognizes Constantine I as senior emperor and executes Valerius Valens.
- Sixteen Kingdoms: Jingwen (later Yuan of Jin) flees with remnants of the Jin court and noble families to the south. He succeeds Emperor Min of Jin as first ruler of the Eastern Jin Dynasty and decides to make Jiankang (modern Nanjing) his new capital.
- The earliest historically verified reference to tea is recorded, although the Chinese have been drinking the beverage for centuries.
- Valerius Valens, Roman emperor