Year 273 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 Licinus and Canina (or, less frequently, year 481 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 273 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

• Impressed by Rome's
  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...
  
   defeat of Pyrrhus
  Pyrrhus of Epirus
  Pyrrhus or Pyrrhos was a Greek general and statesman of the Hellenistic era. He was king of the Greek tribe of Molossians, of the royal Aeacid house , and later he became king of Epirus and Macedon . He was one of the strongest opponents of early Rome...
  
  , Ptolemy II
  Ptolemy II Philadelphus
  Ptolemy II Philadelphus was the king of Ptolemaic Egypt from 283 BCE to 246 BCE. He was the son of the founder of the Ptolemaic kingdom Ptolemy I Soter and Berenice, and was educated by Philitas of Cos...
  
  sends a friendly embassy. The visit is reciprocated.