|Centuries:||2nd century – 3rd century – 4th century|
|Decades:||230s 240s 250s – 260s – 270s 280s 290s|
|Years:||258 259 260 – 261 – 262 263 264|
|261 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||1014|
|Chinese calendar||庚辰年 (Metal Dragon)
2957 or 2897
— to —
辛巳年 (Metal Snake)
2958 or 2898
|Coptic calendar||−23 – −22|
|- Vikram Samvat||317–318|
|- Shaka Samvat||183–184|
|- Kali Yuga||3362–3363|
|Iranian calendar||361 BP – 360 BP|
|Islamic calendar||372 BH – 371 BH|
|Minguo calendar||1651 before ROC
|Seleucid era||572/573 AG|
|Thai solar calendar||803–804|
Year 261 (CCLXI) 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 Gallienus and Taurus (or, less frequently, year 1014 Ab urbe condita). The denomination 261 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 Gallienus crushes the Alemanni at Milan (possible date).
- Gallienus repeals the edict of 258, which led to the persecution of the Christians.
- Gallienus usurpers: The rebellion of Macrianus Major, Macrianus Minor, and Quietus against Gallienus comes to an end. They march from Asia to Europe but are defeated in Thrace by Gallienus' general Aureolus, and both are killed. Quietus flees to Emesa, where he is killed by Odaenathus of Palmyra.
- Roman–Persian Wars: Balista, Roman usurper, collects ships from Cilician ports and defeats the Persian fleet near Pompeiopolis, capturing the harem of king Shapur I.
- Britain elects to join the Gallic Empire.
- Macrianus Major, Roman usurper
- Quietus, Roman usurper
- Mussius Aemilianus, Roman usurper
- Cheomhae of Silla, Korean ruler