The origin of the city's name is unknown, with several theories already circulating in Antiquity; the least likely is derived from Greek language ???? meaning braveness, courage; more probably the connection is with a root *rum-, "teat", with possible reference to the totem wolf (Latin lupa, a word also meaning "prostitute") that adopted and suckled the cognately-named twins Romulus and Remus. Romulus and Remus are believed to come from the people of Lavinium. Romulus killed Remus and founded Rome. The Basque scholar Manuel de Larramendi thought that the origin could be related to the Basque language word orma (modern Basque horma), "wall".

In the past few decades further progress in the Etruscan language and the archaeology of Italy made the above theories less likely, and made more definitive hypotheses possible. We know now that Etruscan was spoken from what became Rhaetia in the Alps through Etruria to include Latium all the way south to Capua. The Italic tribes intruded into Latium from a core Italic region in the central mountains, into which they had moved from the east coast. Regardless of the circumstances of Rome's founding, its original population was certainly a combination of Etruscan and Italic elements, with the Etruscan predominating. Gradually Italic infiltration increased to a flood and overwhelmed the Etruscans; that is, the Etruscan population within and outside Rome assimilated to Italic.

Etruscan gives us the word Rumach, "from Rome", from which Ruma can be extracted. Its further etymology, as is that of most Etruscan words, remains unknown. That it might mean "teat" is pure speculation. Its later mythological associations cast doubt upon that meaning; after all, none of the original settlers was raised by wolves, and the founders were unlikely to have been familiar with this myth about themselves. The name, Tiberius, may well contain the name of the Tiber. It is believed now to be from an Etruscan name, Thefarie, in which case Tiber would be from *Thefar.

The most telling evidence comes from the people themselves. In the expression, Senatus populusque Romanus, "populus" is of Etruscan origin. The place name, Populonia, is from Etruscan Pupluna or Fufluna. Related to populus is the typical Roman praenomen (personal name) of Publius, from Puplie.

Indeed the whole history of early Rome is the story of the struggle between the original families and the newcomers. The praenomina of those families give them away as Etruscan in origin; for example, Gaius, deriving from Cai. It was used by the Julian gens among others. We do not have a derivation of Julus, the mythical founder of the gens, but he is supposed to have been Etruscan. The Etruscans also had a word for gentes, which was lautun. It is not known if this is the origin of Latins, but the etymologizing of most such words pertaining to early Rome has been difficult and resistive, which is likely to mean that they are not Indo-European.

The behaviour of the Etruscans has led to some confusion. Like Latin, Etruscan is inflected and Hellenized. Like the Indo-Europeans, the Etruscans were patrilineal and patriarchal. Like the Italics, they were war-like. The gladiatorial displays actually evolved out of Etruscan funerary customs. Future studies of Etruscan and more excavations in the region will no doubt clarify the origin of Rome and the Romans even more.