As you can see, in economic terms Northern Italy and Southern Italy are basically two different countries.
Northern Italy is on par with Germany, Benelux and the Northern Europe, and even in better shape than France (except for Ile de France) and Great Britain (except for the London area).
Southern Italy is on par with Greece, Spain (except for Catalonia, which is in an economically better situation that the rest of this country) and the western part of Eastern Europe.
This huge divide, by far the greatest in Europe, dates back to the Italian unification, and even before.
Some revisionist southern historians, like Pino Aprile, wrote books where they blame Northern Italy, and especially Piedmont (seat of House Savoy, who unified Italy), for "exploiting" Southern Italy and "looting" it of its resources.
According to these "historians", before unification Southern Italy (then the Kingdom of the Two Sicilies) was a rich and highly developed country, which was "destroyed" by "northern" looting before unification.
Angry southerners spread this story over the Internet, even via Wikipedia (which, we remember, can be modified by anyone).
But this is completely false; people like Aprile bend history for their agenda, omitting the "thorny" part.
One example. The first Italian railway - the Naples-Portici railway - was built in Southern Italy. This is true; but it is also half of what needs to be said. After the buiding of this line, the development of railways in Southern Italy basically stopped; in Northern Italy, instead, the development of railway lines, which only started a year later (the Napoli-Portici railway was inaugurated in 1839, the Milano-Monza railway in 1840), saw much more expansion. In 1859, a year before unification, there were 99 km of railways in Southern Italu, 800 km in Northern Italy... but "historians" like Pino Aprile won't let you know.
Another example about how much the Kingdom of the Two Sicilies was developed comes from the Bronte massacre, which happened shortly after Garibaldi landed in Sicily (1860). The population of the village of Bronte, believing that the arrivan of Garibaldi meant that the social order would finally change, rebelled and massacred 16 "notables" and landowners, before Garibaldi's second-in-command, Nino Bixio, was sent to suppress the revolt and summarily executed five villagers.
While Bixio's actions were criminal in every respect (as southern historians point out, indicating this first episode as a sign of future Piedmontese repression), what happened in Bronte also show what was the real situation in Southern Italy: an archaic, near-feudal society, where peasants barely managed to survive and were oppressed by aristocrats and landowners. Little had improved since 1750 (when the church ovned up to 65 % of the land of the kingdom). Not exactly what one could expect in what, according to the new Bourbon supporters, was one of the most developed countries in Europe. While industry had (shyly) started to develop on its own in Piedmont, Ligury and Lombardy, the little industries that were born in the South could only start thanks to huge government aids and strict protectionist laws. It is true that they closed down shortly after the unification: but this was not due to "Northern looting"; it was simply the effect of lack of competitivity in an open market.
Finally, according to people like Aprile, before the union the North was poor and indebted and the South richer and developed, therefore thr North (namely, the Kingdom of Sardinia) invaded the south to steal everything.
Putting aside the actual economic situation of Northern and Southern Italy in 1860 (I invite anyone to look for serious economic essays about that), one could pause and start thinking. The armed forces of the allegedly developed and powerful Kingdom of the Two Sicilies were effectively thrashed by 1,000 ill-equipped volunteers led by Garibaldi. Is this the power of a developed country?
Pro-south historians claim that this was possible because the military leaders and the ruling class of the South betrayed their king, selling themselves to the Piedmontese. Let us suppose that this is true: which kind of country has a ruling class which so readily sells itself to the first invader? A rich and developed country, or a third world country?
Sorry to say this, but what I explained above is a perfect example of the reason for the present situation of Southern Italy.
People who deny the reality on principle, because it goes against their agenda - Italy is full of such people - will call me racist. But no such thing as "race" is involved; the matter is cultural. Countless Southerners who moved either to Northern Italy or abroad, and adapted to the local culture, have become hard workers and normal citizens, like anyone else. Also a number of southerners still living in South Italy are honest, hard working people: one could remember that the key figures of the fight against the Mafia, including martyr judges Giovanni Falcone and Paolo Borsellino, were Sicilians themselves.
The problem is that too large a number of their fellow southerners are not.
Work ethic and civic values are a too rare quality there. For the former, one can look at this New York Times article (which, much like too many prejudiced and misinformed Americans, blames this problems on the whole of Italy: but the mentioned factory is near Naples). For the latter, just think of what is said about car driving and respect of the traffic code in Italy: while some bad habits have since spread also to parts of the North, the situation in Southern Italy is just catastrophic: seat belts are used by 75 % in Northern Italy and just 45 % in Southern Italy; helmets, by 99 % in Northern Italy and 76 % in Southern Italy.
Another example is waste sorting. Its ratio is 61 % in Lombardy and over 65 % in Veneto and Trentino, while only 43 % in Campania and just 12 % in Sicily. One may remember that the famous waste management crisis took place in Naples.
Most municipalities which achieve a balanced budget are in Northern Italy; due to the "Stability and Growth Pact", they are unable to use their money, which is sent to "prodigal" municipalities in the South, obviously fueling anti-Southern sentiment. As I already said: there are also Southern municipalities which achieve a balanced budget, of course; but they are too few.
It is quite known that organized crime was born in the south. More and more people are rising against it, but the sight of crowds that, during religious procession, stop to "pay tribute" to mobsters in their houses, are not a good sign.
I leave for you to look where corruption, nepotism, illiteracy, clientelism are more widespread.
If you think that the North has done nothing to help the South to develope, you are wrong. Huge sums of money have been transferred from the North to the South over decades, in an attempt to develop its economy; laws were made to facilitate the development of businesses in the South, even to the detriment of the North. They had little effect.
A final thought, A century ago, only Northwestern Italy was industrialized; Northeastern Italy was a poor, agricultural and underdeveloped area, just like the South was. A land of emigration.
Today, Northeastern Italy is nearly as rich as its Northwestern counterpart, while Southern Italy remains the most poor and underdeveloped part of Western Europe. Maybe because the inhabitants of the former did not waste their time complaining about the past, and instead rolled up their sleeves and started working hard to develop their hand? Too many people in the South just blame their problems on others (Pino Aprile is a prime example, as I wrote above) and wait for somebody else to solve their problems - a result of the clientelistic attitude that for too long has prevailed there. Maybe it is time that thei roll up their sleeves, as well.
And a final dig. Lately, some blogs seem to have engaged in the attempt of stating that Northern and Southern Italy are the same, and the difference comes just from prejudices. Namely:
http://rickzullo.com/north-versus-south-issues-in-italy/
http://survivinginitaly.com/2014/07/30/northern-italians-versus-southern-italians-are-they-really-that-different/
http://girlinflorence.com/2015/04/21/north-vs-the-south-a-united-italy/
What I would like to point out, is that the above-linked blogs make a 'selection' of the comments that they post, so that you can only see prejudiced comment from Northerners. Polite comments that pointed out the huge economic difference have been censored (how do I know? I tried to post one!), because they are against, according to Rick Zullo, the idea that the difference between Northern and Southern Italy is just "hype". Zullo did not lose the occasion to make an actually false and prejudical remark about Italy, stating that "Italians appear to spurn routines in general. In fact, it’s often hard to define routines and schedules in Italy. The frequent scioperi disrupt the work week, a long list of holidays revolving around saints and historic events provide countless ponti (long weekends), and shop hours are erratic and unpredictable (e.g. il giorno di riposo)."
I do not know where this Mr. Zullo lived in Italy, but here where I am - Lombardy - shops, stores and lots of businesses nowadays are open even on saturdays and festivities. Scioperi (strikes) are very rare, except for the railways, that are a world of their own, and there are no more than four or five ponti per year. A more accurate research would show you that holidays in Italy are not more numerous than in the rest of Europe.
But Mr. Zullo, unlike the Northerners whom he attacks, is truly a prejudiced cafone.
