Re: Event of the Year
 

419 BC

Despite the Peace of Nicias still being in effect, Sparta's King Agis II gathers a strong army at Philus and descends upon Argos by marching at night from the north. His allied Boeotian forces fail him, but he is able to conclude a treaty with Argos

Greece

Re: Event of the Year
 

420 BC

The young and popular Alcibiades is elected "Strategos" (one of a board of ten generals) and begins to dominate Athenian life and politics. A Quadruple Alliance of Athens, Argos, Mantineia and Elis, which has been organised by Alcibiades (in opposition to Nicias) confronts a Spartan-Boeotian alliance.

Re: Event of the Year
 

421 BC

The construction of the Porch of the Maidens (the Caryatid Porch) commences at the Erechtheion which is part of the Acropolis in Athens

Re: Event of the Year
 

422 BC

Athenian leader, Cleon, ends the truce between Athens and Sparta after he resolves to rescue the town of Amphipolis in Macedonia. However, through skillful generalship by Brasidas, the Spartans rout the Athenians in the Battle of Amphipolis. Both Brasidas and Cleon are killed in the battle, thereby removing the key members of the pro-war factions on both sides.

Re: Event of the Year
 

423 BC

The Athenian general, Laches, successfully moves in the Athenian Assembly for an armistice with Sparta to check the progress of Sparta's most effective general, Brasidas. However, the "Truce of Laches" has little impact on Brasidas and collapses within a year.

Re: Event of the Year
 

424 BC

Demosthenes and Hippocrates attempt to capture Megara, but they are defeated by the Spartans under their general Brasidas. Demosthenes then marches to Naupactus to assist in a democratic revolution, and to gather troops for an invasion of Boeotia. However, Demosthenes and Hippocrates are unable to coordinate their attacks and Hippocrates is defeated at the Battle of Delium by Pagondas of Thebes. During the battle, Socrates is said to have saved the life of Alcibiades. Demosthenes attacks Sicyon and is defeated as well.

Re: Event of the Year
 

425 BC

Demosthenes captures and fortifies the port of Pylos in the Peloponnesus, giving Athens a strong base close to Sparta. Meanwhile, a Spartan army, commanded by Brasidas, lands on the nearby island of Sphacteria, but is repulsed by the Athenians. An Athenian fleet summoned by Demosthenes bottles up the Spartan navy in Navarino Bay.

Re: Event of the Year
 

426 BC

The Athenian leader Cleon and Athenian general Demosthenes revitalise the city's military and naval forces despite opposition from Nicias, a rich merchant and soldier, and his supporters.

Re: Event of the Year
 

427 BC

In an effort to blockade Sparta from access to Sicilian corn, Athens responds to a plea for help from a delegation from the city of Leontini led by Gorgias, the sophist and rhetorician. Leontini is being threatened by Syracuse which is allied to Sparta. However, the Athenian mission led by the Athenian general Laches is unable to offer much help. Laches is later prosecuted by Cleon for his unsuccessful mission to support Athenian interests in Sicily.

Re: Event of the Year
 

428 BC

The Greek colony of Cumae in Italy falls to the Samnites, who begin to take control of the Campanian plain


Italy