How did the Colosseum get its name?
As one of Rome's most popular landmarks, both ancient and contemporary, the Colosseum is visited by millions of visitors each year. A 2014 Travel and Leisure magazine article reported, in fact, that more than 5 million tourists traversed the intricate vaults of the Colosseum that year . When it was first built, though, the famous amphitheater held a different name, one that served as a reminder of the man who built it. Interestingly, the name it now holds is connected to another, a more fiendish man that Rome wanted to forget.
When the Roman Emperor Nero took power in October 54 CE, one could have assumed greatness would ensue as he was a descendent from the Julio-Claudian family line, a lineage that traced back to Julius Caesar. The result of Nero's rule, however, was far from rosy. From the murder of his mother in 59 BCE to his growing conflicts with the Roman Senate in the years following, Nero's control of Rome was rather tumultuous 
These tensions came to a head in July 64 CE, when a raging fire broke out and burned across the city of Rome for almost a week.  While interpretations of how Nero responded to the blaze and its aftermath vary, it is clear that Nero was tasked with rebuilding substantial portions of the city in the midst of the city's recovery. In this project, Nero planned a massive new palace complex for himself. Know as the Domus Aurea, or "Golden House," the fantastically decorated palace stretched across the heart of the Roman Forum. Including lavish reflecting ponds and a monumental bronze sculpture of the god Sol that stood just outside its main entrance, the Domus Aurea irked many Romans as it consumed a significant amount of land that was previously used for the citizens.
Vespasian and Flavian Favoritism
Soon after his brilliant new home was built, Nero was condemned to death, and the doomed ruler committed suicide on 9 June 68 CE.  In his stead, Emperor Vespasian had taken control of Rome one year prior (July 69 CE). His task was to reassure Rome's citizens that imperial rule was reliable and just. As part of this reassurance, and to win favor with the Romans, Vespasian embarked on constructing a massive entertainment amphitheater, a wish of Roman citizens for many years.
Construction on the complex began in 72 CE, with Vespasian selecting a location at the juncture of three of Rome's hills: the Palatine, the Esquiline, and the Caelian. Conveniently, to facilitate this location, Vespasian requested the demolition of much of Nero's Domus Aurea such that his theater would quite literally rest on the ruins of Nero's reign.
The amphitheater was a massive project and was designed to seat over 55,000 people. The amphitheater's construction was funded with the spoils seized from the Jewish Temple after Roman crushed the Jewish Revolt of 70 AD. Stolen Jewish artifacts not only funded the building of the Colosseum, but Jewish slaves seized during the revolt built the building.
A Lingering Colossus
Work progressed on the amphitheater for the following eight years and thus stretched across several Vespasian's successors, known to history as the Flavian dynasty. Because of the sharing of this project, the amphitheater took the name of the "Flavian Amphitheater," and the citizens of Rome received its debut joyously. With a capacity for tens of thousands of audience members and novel features that allow for feats as fantastic as mock naval battles in the main arena, the amphitheater became a hub for Roman entertainment.
While Vespasian and his successors received the Romans' favor for this monumental contribution, a lasting remnant of Nero's disastrous rule still stood close by. That colossal sculpture of Sol had been preserved by Vespasian and moved closer to the Flavian Amphitheater's main entrance. As time passed, this prominent Colossus became so inextricably connected to the amphitheater that the name of "Colosseum" came into common parlance soon after.
So, while the efforts to manifest the impressive amphitheater were the work of the Flavian emperors, in some regards, one could suggest that Nero's legacy also lives on with this connection to his Colossus. This massive statue, though, has long since disappeared. Last mentioned in an illuminated manuscript from the fourth century CE, it is unclear what happened to the Sol sculpture.  It was most likely destroyed or melted down; its pedestal adjacent to the Colosseum, however, still stands today.
- "The World's Most-visited Tourist Attractions"Travel and Leisure Magazine. 10 November 2014.
- Barrett, Anthony A., "Nero."The Oxford Encyclopedia of Ancient Greece and Rome. (Oxford University Press, 2010)
- Dando-Collins, Stephen. The Great Fire of Rome (Da Capo Press, 2010).
- Suetonius,The Lives of the Twelve Ceasars (Loeb Classical Library, 1914), p. 179)
- "Building the Colosseum," www.tribunesandtriumphs.org
- Calendar of 354 http://www.tertullian.org/fathers/index.htm#Chronography_of_354
Updated, December 5, 2020