Editing 5th century BC (section)

===[[410s BC]]===
* [[419 BC]]: The [[Peace of Nicias]] is broken when Sparta defeats [[Argos, Peloponnese|Argos]].
* [[418 BC]]: The Spartans win a major victory over the Athenians in the [[Battle of Mantinea (418 BC)|Battle of Mantinea]], the biggest land battle of the [[Peloponnesian War]].
* [[416 BC]]: The Athenians capture the island of [[Melos]] and treat the inhabitants with great cruelty.
* [[416 BC]]: The Athenians adhere to a plea of help from [[Sicily]] and start planning an invasion of the island.
* [[415 BC]]: The sacred [[Herma]]e busts in Athens are mutilated just before the expedition to Sicily is sent away. One of the culprits, [[Andocides]], is captured and is forced to turn informer. He names the other mutilators, among them Alcibiades, who are sentenced to death in their absence.
* [[415 BC]]: Alcibiades defects from Athens to Sparta after having learned about his death sentence.
* [[414 BC]]: The Athenians try to make a breakthrough in [[Sicilian Expedition|their siege]] of [[Syracuse, Sicily|Syracuse]] but are defeated by the Spartans.
* [[413 BC]]: [[Nāgadāsaka|Nagadaska]] is deposed by people of [[Magadha (Mahajanapada)|Magadha]]. Thus, ending [[Haryanka dynasty]]. He succeeded by [[Shishunaga]] who founded [[Shaishunaga dynasty]].
* [[413 BC]]: [[Demosthenes (general)|Demosthenes]] suggests the Athenians leave Syracuse in order to return to Athens, where help is needed. However, [[Nicias]] refuses and they are again [[Battle of Syracuse (415 BC)|defeated in battle]] by the Spartans. Both Demosthenes and Nicias are killed.
* [[413 BC]]: [[Caria]] allies itself with Sparta.
* [[412 BC]]: The [[Achaemenid Empire|Persian Empire]] starts preparing an invasion of [[Ionia]] and signs a treaty with [[Sparta]] about it.
* [[411 BC]]: The democracy in Athens is overthrown and replaced by the oligarchic [[The Four Hundred (oligarchy)|Council of Four Hundred]]. This council is itself soon defeated and order is almost restored, when the Five Thousand start ruling. Early next year, they are also overthrown and the old democracy is restored.
* [[410 BC]]: Athens regains control over its vital grain route from the [[Black Sea]] by defeating Sparta in the [[Battle of Cyzicus]].