|301 by topic|
|Ab urbe condita||1054|
|Balinese saka calendar||222–223|
|Chinese calendar||庚申年 (Metal Monkey)|
2997 or 2937
— to —
辛酉年 (Metal Rooster)
2998 or 2938
|- Vikram Samvat||357–358|
|- Shaka Samvat||222–223|
|- Kali Yuga||3401–3402|
|Iranian calendar||321 BP – 320 BP|
|Islamic calendar||331 BH – 330 BH|
|Minguo calendar||1611 before ROC|
|Seleucid era||612/613 AG|
|Thai solar calendar||843–844|
427 or 46 or −726
— to —
428 or 47 or −725
Year 301 (CCCI) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Postumius and Nepotianus (or, less frequently, year 1054 Ab urbe condita). The denomination 301 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.
- Emperor Diocletian issues his Edict on Maximum Prices, which, rather than halting rampant inflation and stabilizing the economy, over time adds to inflationary pressures, by flooding the economy with new coinage, and by setting price limits too low.
- Diocletian begins the construction of new roads in the Roman Empire. The Strata Diocletiana is built, and lined with a series of forts (quadriburgia); it runs from the Gulf of Aqaba (Arabia) to the Euphrates.
- King Tiridates III of Armenia proclaims Christianity as the official state religion, making Armenia the first nation to adopt Christianity as its official religion. Construction of the original Etchmiadzin Cathedral by Gregory the Illuminator begins.
- C.W. Dugmore, The Journal of Ecclesiastical History (Cambridge University Press) p.268.
- A. Dzh. (Arman Dzhonovich) Kirakosian, The Armenian Massacres, 1894–1896: 1894–1896 : U.S. media testimony, p.131.
- "OrientalOrthodox.org". Archived from the original on July 27, 2011. Retrieved March 4, 2010.
- Johann Christian Wilhelm Augusti, Georg Friedrich Heinrich Rheinwald, Carl Christian Friedrich Siegel, The Antiquities of the Christian Church p.466.