|Centuries:||3rd century – 4th century – 5th century|
|Decades:||360s 370s 380s – 390s – 400s 410s 420s|
|Years:||394 395 396 – 397 – 398 399 400|
|397 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||1150|
|Chinese calendar||丙申年 (Fire Monkey)
3093 or 3033
— to —
丁酉年 (Fire Rooster)
3094 or 3034
|- Vikram Samvat||453–454|
|- Shaka Samvat||319–320|
|- Kali Yuga||3498–3499|
|Iranian calendar||225 BP – 224 BP|
|Islamic calendar||232 BH – 231 BH|
|Minguo calendar||1515 before ROC
|Seleucid era||708/709 AG|
|Thai solar calendar||939–940|
Year 397 (CCCXCVII) was a common year starting on Thursday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Caesarius and Atticus (or, less frequently, year 1150 Ab urbe condita). The denomination 397 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.
- Stilicho drives the Visigoths out of Greece and Macedonia. King Alaric I escapes to Epirus in the Balkans.
- The Xiongnu occupy the Gansu area, the economically important province is situated along the Silk Road.
- April 4 – Ambrose, Archbishop of Milan, dies in his diocese after 23 years in office during which he dominated the political life of the Roman Empire.
- August 28 – Council of Carthage: The biblical canon is definitely declared.
- September 7 – First Council of Toledo: Hispanic bishops, including Lampius, condemn Priscillianism.
- November 13 – John Chrysostom is appointed Archbishop of Constantinople.
- Mor Gabriel Monastery is founded and located on the Tur Abdin plateau near Midyat (Turkey).
- Sulpicius Severus writes the earliest biography of Martin of Tours, the first known "life of a saint" ever written.
- Augustine of Hippo begins his Confessions, an autobiography that recounts his intellectual and spiritual development.
- Scottish missionary Ninian establishes a church (Candida Casa) at Whithorn, and begins his work among the Picts.
- April 4 – Aurelius Ambrosius, bishop of Milan
- November 11 – Martin of Tours, bishop and saint
- Murong Hui, imperial prince of Later Yan (b. 373)
- Murong Long, general and prince of Later Yan
- Empress She, wife of emperor Yao Chang