Year 422 BC was a year of the pre-Julian Roman calendar

Roman calendar

The Roman calendar changed its form several times in the time between the founding of Rome and the fall of the Roman Empire. This article generally discusses the early Roman or pre-Julian calendars...

. At the time, it was known as the Year of the Tribunate of Capitolinus, Mugillanus and Merenda (or, less frequently, year 332 Ab urbe condita

Ab urbe condita

Ab urbe condita is Latin for "from the founding of the City ", traditionally set in 753 BC. AUC is a year-numbering system used by some ancient Roman historians to identify particular Roman years...

). The denomination 422 BC for this year has been used since the early medieval period, when the Anno Domini

Anno Domini

and Before Christ are designations used to label or number years used with the Julian and Gregorian calendars....

 calendar era

Calendar era

A calendar era is the year numbering system used by a calendar. For example, the Gregorian calendar numbers its years in the Western Christian era . The instant, date, or year from which time is marked is called the epoch of the era...

 became the prevalent method in Europe for naming years.

Greece

• Athenian leader, Cleon
  Cleon
  Cleon was an Athenian statesman and a Strategos during the Peloponnesian War. He was the first prominent representative of the commercial class in Athenian politics, although he was an aristocrat himself...
  
  , ends the truce between Athens
  Athens
  Athens , is the capital and largest city of Greece. Athens dominates the Attica region and is one of the world's oldest cities, as its recorded history spans around 3,400 years. Classical Athens was a powerful city-state...
  
   and Sparta
  Sparta
  Sparta or Lacedaemon, was a prominent city-state in ancient Greece, situated on the banks of the River Eurotas in Laconia, in south-eastern Peloponnese. It emerged as a political entity around the 10th century BC, when the invading Dorians subjugated the local, non-Dorian population. From c...
  
   after he resolves to rescue the town of Amphipolis
  Amphipolis
  Amphipolis was an ancient Greek city in the region once inhabited by the Edoni people in the present-day region of Central Macedonia. It was built on a raised plateau overlooking the east bank of the river Strymon where it emerged from Lake Cercinitis, about 3 m. from the Aegean Sea. Founded in...
  
   in Macedon
  Macedon
  Macedonia or Macedon was an ancient kingdom, centered in the northeastern part of the Greek peninsula, bordered by Epirus to the west, Paeonia to the north, the region of Thrace to the east and Thessaly to the south....
  
  ia. However, through skillful generalship by Brasidas
  Brasidas
  Brasidas was a Spartan officer during the first decade of the Peloponnesian War.He was the son of Tellis and Argileonis, and won his first laurels by the relief of Methone, which was besieged by the Athenians . During the following year he seems to have been eponymous ephor Brasidas (died 422...
  
  , the Spartans rout the Athenians in the Battle of Amphipolis
  Battle of Amphipolis
  The Battle of Amphipolis was fought in 422 BC during the Peloponnesian War between Athens and Sparta. It was the culmination of events that began in 424 BC with the capture of Amphipolis by the Spartans.-Capture of Amphipolis, 424–423 BC:...
  
  . Both Brasidas and Cleon are killed in the battle, thereby removing the key members of the pro-war factions on both sides.
• Alcibiades
  Alcibiades
  Alcibiades, son of Clinias, from the deme of Scambonidae , was a prominent Athenian statesman, orator, and general. He was the last famous member of his mother's aristocratic family, the Alcmaeonidae, which fell from prominence after the Peloponnesian War...
  
  takes over the leadership of the pro-war party in Athens.