alternatehistory.com

That was what I picked up from one foodies forum; Nepolitant style pizza, made with tomato-based sauce and cheese topping was primarily a Southern Italian dish, but now avalible throughout Italy because of tourism boom postwar.

The reason was American tourists, who were brought up with southern Italian dishes introduced to them by Southern Italian immigrants for so long they assume this is regular Italian dish. Large number of them came to Italy in the 50's and expecting pizza to be served in any restaurant, including Northern ones. So eateries throughout Italy start serving this style of pizza to cater to tourists' demand. The rest is history.

Is this story true?

If not, what had to happened back in time to confine Nepolitant pizza in the South, and pizzerias as we know it only become widespread throughout Italy because of tourist industry.
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