Year 173 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 Consulship of Albinus and Laenas (or, less frequently, year 581 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 173 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.

Egypt

• Ptolemy VI Philometor
  Ptolemy VI Philometor
  Ptolemy VI Philometor was a king of Egypt from the Ptolemaic period. He reigned from 180 to 145 BC....
  
   marries his sister, Cleopatra II
  Cleopatra II of Egypt
  Cleopatra II was a queen of Ptolemaic Egypt.-Family:Cleopatra II was the daughter of Ptolemy V and likely Cleopatra I. She was the sister of Ptolemy VI and Ptolemy VIII Euergetes II Tryphon. She would eventually marry both of her brothers.Her first marriage was with her brother Ptolemy VI in ca....
  
  .

Seleucid Empire

• Antiochus IV
  Antiochus IV Epiphanes
  Antiochus IV Epiphanes ruled the Seleucid Empire from 175 BC until his death in 164 BC. He was a son of King Antiochus III the Great. His original name was Mithridates; he assumed the name Antiochus after he ascended the throne....
  
   pays the remainder of the war indemnity
  Indemnity
  An indemnity is a sum paid by A to B by way of compensation for a particular loss suffered by B. The indemnitor may or may not be responsible for the loss suffered by the indemnitee...
  
   that has been imposed by the Romans
  Roman Republic
  The Roman Republic was the period of the ancient Roman civilization where the government operated as a republic. It began with the overthrow of the Roman monarchy, traditionally dated around 508 BC, and its replacement by a government headed by two consuls, elected annually by the citizens and...
  
   on Antiochus III
  Antiochus III the Great
  Antiochus III the Great Seleucid Greek king who became the 6th ruler of the Seleucid Empire as a youth of about eighteen in 223 BC. Antiochus was an ambitious ruler who ruled over Greater Syria and western Asia towards the end of the 3rd century BC...
  
   in the Treaty of Apamea
  Treaty of Apamea
  The Treaty of Apamea of 188 BC, was peace treaty between the Roman Republic and Antiochus III , ruler of the Seleucid Empire. It took place after the Romans' victories in the battle of Thermopylae , in the Battle of Magnesia , and after Roman and Rhodian naval victories over the Seleucid navy.In...
  
   (188 BC
  188 BC
  Year 188 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Messalla and Salinator...
  
  ).

Births

• Antiochus V Eupator, ruler of the Seleucid Empire
  Seleucid Empire
  The Seleucid Empire was a Greek-Macedonian state that was created out of the eastern conquests of Alexander the Great. At the height of its power, it included central Anatolia, the Levant, Mesopotamia, Persia, today's Turkmenistan, Pamir and parts of Pakistan.The Seleucid Empire was a major centre...
  
   from 164 BC
  164 BC
  Year 164 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 Longinus...
  
   (d. 162 BC
  162 BC
  Year 162 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Corculum/Lentulus and Figulus/Ahenobarbus...
  
  )