340 BC

Millennium:	1st millennium BC
Centuries:	5th century BC – 4th century BC – 3rd century BC
Decades:	370s BC 360s BC 350s BC – 340s BC – 330s BC 320s BC 310s BC
Years:	343 BC 342 BC 341 BC – 340 BC – 339 BC 338 BC 337 BC

340 BC by topic
Politics
State leaders – Sovereign states
Birth and death categories
Births – Deaths
Establishments and disestablishments categories
Establishments – Disestablishments

340 BC in other calendars
Gregorian calendar	340 BC
Ab urbe condita	414
Armenian calendar	N/A
Assyrian calendar	4411
Bahá'í calendar	-2183–-2182
Bengali calendar	-932
Berber calendar	611
English Regnal year	N/A
Buddhist calendar	205
Burmese calendar	-977
Byzantine calendar	5169–5170
Chinese calendar	庚辰年 (2297/2357) — to — 辛巳年 (2298/2358)
Coptic calendar	-623–-622
Ethiopian calendar	-347–-346
Hebrew calendar	3421–3422
Hindu calendars
- Vikram Samvat	-283–-282
- Shaka Samvat	N/A
- Kali Yuga	2762–2763
Holocene calendar	9661
Iranian calendar	961 BP – 960 BP
Islamic calendar	991 BH – 990 BH
Japanese calendar
Korean calendar	1994
Minguo calendar	2251 before ROC 民前2251年
Thai solar calendar	204

Year 340 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Torquatus and Mus (or, less frequently, year 414 Ab urbe condita). The denomination 340 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.

Events

By place

Persian Empire

Rhodes falls to Persian forces.
Pixodarus, the youngest of the three sons of King Hecatomnus of Caria, gains possession of the satrapy of Caria by expelling his sister Ada, the widow and successor of her brother Idrieus.

Greece

When King Philip II of Macedon attacks Perinthus and Byzantium, King Artaxerxes III of Persia sends support to those cities.
Philip II fails in his siege of Byzantium and is forced to respond to attacks by the Scythians near the mouth of the Danube. His son, Alexander is regent while his father fights against Byzantium and the Scythians.
The Athenians give Demosthenes a public vote of thanks after Philip's unsuccessful siege of Byzantium.

Sicily

Hicetas, the tyrant of Leontini, again persuades Carthage to send a large army to Sicily, which lands at Lilybaeum. Timoleon of Syracuse meets this large Carthaginian army in the Battle of the Crimissus in the west of Sicily and achieves a brilliant victory against superior odds. Despite this victory, the Carthaginians continue to occupy the western half of Sicily, with a treaty being concluded that confines the Carthaginians to the area west of the Halycus (Platani) River.

Roman Republic

An embassy is sent by the Latin peoples to the Roman Senate asking for the formation of a single republic between Rome and Latium, in which both parties would be considered to be equal. As Rome considers that it is the leader of the Latin League, it refuses to treat the Latin people as being equal politically or have Latin people in the Roman Senate. With Rome's refusal of the proposal, the Latin War begins. The Latins fight with the Campanians, while Rome joins the Samnites to attack the Latins. Only the Laurentes in Latium and the equites of Campania remain with the Romans, who, for their part, find support among the Paeligni.
The Roman-Samnite army under consuls Decius Mus and Titus Manlius Torquatus attack and defeat the Latins and Campanians near Mount Vesuvius in the Battle of Vesuvius.
The Romans succeed in detaching the Campanians from their alliance with the Latins (through their fear of the Samnites) and induce them to make a separate peace. Three Campanian cities, including Capua and Cumae, are granted Roman citizenship and thus become part of the Roman state. The Roman state now extends to the Bay of Naples.