The year 525 BC was a year of the pre-Julian Roman calendar. In the Roman Empire, it was known as year 229 Ab urbe condita. The denomination 525 BC 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.
|Millennium:||1st millennium BC|
|Gregorian calendar||525 BC|
|Ab urbe condita||229|
|Ancient Egypt era||XXVII dynasty, 1|
|- Pharaoh||Cambyses II of Persia, 1|
|Ancient Greek era||63rd Olympiad, year 4|
|Balinese saka calendar||N/A|
|Chinese calendar||乙亥年 (Wood Pig)|
2172 or 2112
— to —
丙子年 (Fire Rat)
2173 or 2113
|Coptic calendar||−808 – −807|
|Ethiopian calendar||−532 – −531|
|- Vikram Samvat||−468 – −467|
|- Shaka Samvat||N/A|
|- Kali Yuga||2576–2577|
|Iranian calendar||1146 BP – 1145 BP|
|Islamic calendar||1181 BH – 1180 BH|
|Minguo calendar||2436 before ROC|
|Thai solar calendar||18–19|
−398 or −779 or −1551
— to —
−397 or −778 or −1550
- Battle of Pelusium - Cambyses II of Persia conquers Egypt by painting cats and other animals sacred to the Egyptians on his soldiers' shields. The Egyptians run in fear of "harming" these animals. It is said that after the battle, Cambyses hurled cats in the faces of the Egyptians in scorn that they would sacrifice their country for the safety of their animals.
- Cambyses takes Psamtik III prisoner and treats him kindly until he tries to raise a revolt, at which point Psamtik is executed.
- The Twenty-sixth Dynasty ends, and the Twenty-seventh Dynasty begins.