405 BC

405 BC in various calendars
Gregorian calendar	405 BC; CDV BC
Ab urbe condita	349
Ancient Egypt era	XXVII dynasty, 121
- Pharaoh	Darius II of Persia, 19
Ancient Greek era	93rd Olympiad, year 4
Assyrian calendar	4346
Balinese saka calendar	N/A
Bengali calendar	−997
Berber calendar	546
Buddhist calendar	140
Burmese calendar	−1042
Byzantine calendar	5104–5105
Chinese calendar	乙亥年 (Wood Pig); 2293 or 2086; — to —; 丙子年 (Fire Rat); 2294 or 2087
Coptic calendar	−688 – −687
Discordian calendar	762
Ethiopian calendar	−412 – −411
Hebrew calendar	3356–3357
Hindu calendars
- Vikram Samvat	−348 – −347
- Shaka Samvat	N/A
- Kali Yuga	2696–2697
Holocene calendar	9596
Iranian calendar	1026 BP – 1025 BP
Islamic calendar	1058 BH – 1057 BH
Javanese calendar	N/A
Julian calendar	N/A
Korean calendar	1929
Minguo calendar	2316 before ROC; 民前2316年
Nanakshahi calendar	−1872
Thai solar calendar	138–139
Tibetan calendar	阴木猪年; (female Wood-Pig); −278 or −659 or −1431; — to —; 阳火鼠年; (male Fire-Rat); −277 or −658 or −1430

250 BC in various calendars
Gregorian calendar	250 BC; CCL BC
Ab urbe condita	504
Ancient Egypt era	XXXIII dynasty, 74
- Pharaoh	Ptolemy II Philadelphus, 34
Ancient Greek era	132nd Olympiad, year 3
Assyrian calendar	4501
Balinese saka calendar	N/A
Bengali calendar	−842
Berber calendar	701
Buddhist calendar	295
Burmese calendar	−887
Byzantine calendar	5259–5260
Chinese calendar	庚戌年 (Metal Dog); 2448 or 2241; — to —; 辛亥年 (Metal Pig); 2449 or 2242
Coptic calendar	−533 – −532
Discordian calendar	917
Ethiopian calendar	−257 – −256
Hebrew calendar	3511–3512
Hindu calendars
- Vikram Samvat	−193 – −192
- Shaka Samvat	N/A
- Kali Yuga	2851–2852
Holocene calendar	9751
Iranian calendar	871 BP – 870 BP
Islamic calendar	898 BH – 897 BH
Javanese calendar	N/A
Julian calendar	N/A
Korean calendar	2084
Minguo calendar	2161 before ROC; 民前2161年
Nanakshahi calendar	−1717
Seleucid era	62/63 AG
Thai solar calendar	293–294
Tibetan calendar	阳金狗年; (male Iron-Dog); −123 or −504 or −1276; — to —; 阴金猪年; (female Iron-Pig); −122 or −503 or −1275

Events

After their victory in the Battle of Arginusae over the Spartans, the Athenian fleet follows the reappointed Spartan admiral, Lysander, to the Hellespont. The Athenian fleet under Admiral Conon is destroyed by the Spartans under Lysander in the Battle of Aegospotami in the Sea of Marmara and Conon flees to Cyprus.
The Spartan king Pausanias lays siege to Athens while Lysander's fleet blockades Piraeus. This action closes the grain route through the Hellespont, thereby starving Athens.
While the Peloponnesians besiege Athens, Theramenes tries to negotiate with Lysander. He is away for three months while Athens is being reduced to starvation. Then he heads the embassy that negotiates the terms of capitulation to the Spartans.

Dionysius the Elder rises to power as the tyrant of Syracuse. He makes peace with the Carthaginian general, Hamilco (whose army has been weakened by the plague), and fortifies Syracuse. This treaty leaves Carthage in control of most of Sicily.
Dionysius the Elder ruthlessly consolidates and expands his power. He builds a wall around Syracuse and fortifies Epipolae. The Greek citizens of Naxos, Catana, and Leontini are removed from their cities; many of them are enslaved and their homes are given to Sicilian and Italian mercenaries. Dionysius prepares his army to fight against Carthage, which now occupies western and southern Sicily.

Aristophanes' play The Frogs is performed.
Euripides' The Bacchae and Iphigeneia at Aulis are performed posthumously as part of a tetralogy at the City Dionysia festival and win first prize.

The Erechtheum, which includes The Porch of Maidens (Caryatid Porch), is completed in the Ionian style on the Acropolis in Athens after 16 years of construction.

Philolaus, Greek mathematician and philosopher (approximate date) (b. c. 480 BC)