Romans come from Rome. Sardinians come from Sardinia. And Venetians come from Venice. But how do Italians refer to themselves in their native language?

The name used by natives themselves is called either an endonym, autonym, or self-appellation. In Italian, the term endonimo is rarely used. Much more frequently encountered is the phrase denominazione abitanti. Some Italian examples include romano, sardo, and veneziano.

Conversely, terms such as Neapolitan and Florentine are exonyms—a name given to a group or category of people that is not used within that place by the local inhabitants (neither in the official language of the state nor in local languages). In other words, you'll never hear a fiorentino (a native of Florence) refer to himself as a Florentine. The word Florentine is an English word used by English speakers in their native tongue.

But what about your uncle from Basilicata, who is frequently called il lucano, or your friend Giuseppina, who refers to herself as una partenopea verace?

Italian Regional Endonyms
Below is a list of the twenty Italian regions and the term used to refer to either a native or an inhabitant of that region (regione):

Abruzzo: abruzzese
Basilicata: lucano (less common: basilicatese)
Calabria: calabrese
Campania: campano
Emilia-Romagna: emiliano / romagnolo
Friuli-Venezia Giulia: friulano / giuliano
Lazio: laziale
Liguria: ligure
Lombardia: lombardo
Marche: marchigiano
Molise: molisano
Piemonte: piemontese
Puglia: pugliese
Sardegna: sardo
Sicilia: siciliano
Toscana: toscano
Trentino-Alto Adige: trentino / altoatesini
Umbria: umbro
Valle d'Aosta: valdostano
Veneto: veneto

Note that the above Italian endonyms are in the singular masculine form. The rules for creating plural forms are comparable to those for forming other Italian plural nouns. As an example, a siciliano is a Sicilian man, while a woman from Sicily would be referred to as a siciliana. A group of two or more Sicilian people, with at least one man in the group, would be referred to as siciliani, and a group of two or more Sicilian women are siciliane.

In perusing the list of Italian regional endonyms it's obvious that certain patterns emerge (the common suffixes –ano and –ese immediately come to mind). But what about lucano, the preferred term for Basilicatan natives? In fact, the name originates from Lucania, the ancient name used during the Roman era for the region.

Italian Town and City Endonyms
Below is a list of various Italian towns and cities and the term used to refer to either a native or an inhabitant of that town or city (città):

Bari: barese
Bergamo: bergamasco
Bologna: bolognese
Brescia: bresciano
Catania: catanese
Chieve: chievese
Chioggia: chioggiotto
Firenze: fiorentino
Frosinone: frusinato
Genova: genovese
Ivrea: eporediese (from the ancient Roman name of the city)
La Spezia: spezzino
Messina: messinese
Milano: milanese
Modena: modenese
Napoli: napoletano (or partenopeo)
Padova: padovano
Palermo: palermitano
Pantelleria: pantescho
Perugia: perugino
Prato: pratese
Ravenna: ravegnano / ravennato
Reggio Calabria: reggino
Roma: romano
Susegana: suseganese
Taranto: tarantino
Torino: torinese
Torretta: torrittese
Trieste: triestino
Val di Vizze: valvizzese
Venezia: veneziano
Verona: veronese
Zafferana Etnea: zafferanese

To parse out the term partenopeo (referring to a native of Napoli) a bit of Greek mythology is necessary. Parthenope was the name of the ancient Greek settlement which is now present-day Napoli. The town (Parthenope) was named after the siren in Greek mythology said to have washed ashore at Megaride after throwing herself into the sea when she failed to bewitch Odysseus with her song.

Around the 5th century BC, the area was occupied by Greek colonists, who displaced the original inhabitants to the east where they founded Neapolis (meaning "new town" in the Greek language). The original Parthenope came to be called, simply, "old city"—Palaeopolis. The two separate cities grew into a single unit in the 3rd century BC. Although later conquered by the Romans, Naples long retained its Greek culture.