Recording previous names of cities/provinces

[Amansolillo]

Hello all,

I recently realized that for quite some time, I have still been using the modern names of cities and provinces in my family tree for some locations whose names have changed over time. This has been a bit problematic, as I am currently working in the 1700s, but most of my data is recorded using the modern names of cities. Over time I have tried to fix it, but I don't know the exact date when certain names were changed, and in some cases, the previous names of cities at all.

Some examples of what I am talking about:
(Current name) - Itri, Latina, Lazio, Italy
(1815) - Itri, Terra di Lavoro, Campania, Kingdom of Naples

(Current name) - Piedimonte Matese, Caserta, Campania, Italy
(1820) - Piedimonte d'Alife, Terra di Lavoro, Campania, Kingdom of Naples

(Current name) - Letino, Caserta, Campania, Italy
(1886?) - Letino, Campobasso, Molise, Italy

The following cities/provinces I am currently trying to find the previous names for throughout time:

*Panni, Foggia, Puglia, Italy (early-middle 1800s - Panni, Capitanata, Puglia, Italy)
*Orsara di Puglia, Foggia, Puglia, Italy (previously called Orsara Dauno Irpino)
*Ariano Irpino, Avellino, Campania, Italy (previously called Ariano and Ariano di Puglia)
*Savignano Irpino, Avellino, Campania, Italy (previously called Savignano and Savignano di Puglia)
*Roccapiemonte, Salerno, Campania, Italy
*Itri, Latina, Lazio, Italy (around 1900 - Itri, Caserta, Campania, Italy/1800s - Itri, Terra di Lavoro, Campania, Kingdom of Naples)
*Monte San Biagio, Latina, Lazio, Italy (1800s - Monticelli, Terra di Lavoro, Campania, Kingdom of Naples)
*Valmontone, Roma, Lazio, Italy
*Ceprano, Frosinone, Lazio, Italy (late 1800s - Ceprano, Roma?, Lazio, Italy)
*Arce, Frosinone, Lazio, Italy
*Colle San Magno, Frosinone, Lazio, Italy
*Pontecorvo, Frosinone, Lazio, Italy (1800s - Pontecorvo, Terra di Lavoro?, Campania?, Kingdom of Naples)
*Letino, Caserta, Campania, Italy (late 1800s - Letino, Campobasso, Molise, Italy)
*Prata Sannita, Caserta, Campania, Italy (1800s - Prata [Sannita]?, Terra di Lavoro, Campania, Kingdom of Naples)
*Piedimonte Matese, Caserta, Campania, Italy (1800s - Piedimonte d'Alife, Terra di Lavoro, Campania, Kingdom of Naples)
*San Potito Sannitico, Caserta, Campania, Italy
*Conca della Campania, Caserta, Campania, Italy
*Marzano Appio, Caserta, Campania, Italy (1800s - Marzano?, Terra di Lavoro, Campania, Kingdom of Naples)
*Canicattini Bagni, Siracusa, Sicilia, Italy

I have tried the Italian Wikipedia to find the previous names for several of the listed cities and provinces, but some of the dates were contradictory and confusing.

If at all possible, I would like to know the previous names (in "city, province, region, country" listing) and the years that the city or province was known by that name.

[DCPandaFan]

A lot of comuni changed their names after unification because the national government had complained that there were too many similar place names. Because a lot of comuni had changed their names, there were several "gazetteer" type books published from the late 1860s and 1870s that cross-referenced new vs. old names. Usually the new name comes first, then the word "già", then the old name.
Here is one example book that is online for free:
https://books.google.com/books?id=i1lNAAAAcAAJ
Likewise, provinces and the boundaries of provinces and regions changed over time. Wikipedia will get you what you need to know about these changes.

[PippoM]

I have a list of the communes that changed their name (I think from unification on), but I don't remember where I found it (I think in the site of the Ministry of Interior, but I'm not sure). Also, I have a list of no more existing communes. If you are interested, you can send me a PM.