Traditionally, the date of the founding of Rome by Romulus is April 21, 753 BC. Marcus Julius Verus Philippus was the emperor of Rome in 248 AD when the 1000th anniversary arrived and celebrated with three days of festivities from April 21-23. The Greek historian, Gaius Asinius Quadratus, wrote a 15-volume work entitled “Chilieteris” (“Millenium”), chronicling the city from the founding to the reign of Severus Alexander, and intended to follow through to the reign of Philip, but died before it could be completed.
The celebration took place throughout the city in the forms of theatrical performances, ludi saeculares, and spectacular games in the Colosseum. Gordian III had collected exotic animals for his anticipated triumphal parade over the Persians, but since he failed to defeat them and died while doing so, Philip repurposed the animals for the games. Besides the animals, which were slaughtered, more than 1,000 gladiators also fought to the death in the Colosseum during the games.
The mint in Rome struck coins to commemorate the anniversary, all in the names of Philip, his newly elevated co-augustus son, Philip II, and his wife, Otacilia Severa. The reverse legend on the antoniniani read SAECVLARES AVGG and the six officinae marked the coins with their office numeral. The series was issued as such:
Other coins issued to celebrate the games were not marked by a single officina:
Philip I: AETERNITAS AVGG – Rider goading an elephant
Philip I: SAECVLARES AVGG – Cippus inscribed COS III
Philip I and II: SAECVLVM NOVVM – Statue of Roma in hexastyle temple
Various sources state the coins with the officina marks might have been issued during the time of the festivities and the rest later in the year and into 249 before the end of the year-long celebration of the anniversary.