In which country did pizza originate?

Pizza was first invented in Naples, Italy as a fast, affordable, tasty meal for working-class Neapolitans on the go. While we all know and love these slices of today, pizza actually didn’t gain mass appeal until the 1940s, when immigrating Italians brought their classic slices to the United States. While topped flatbreads were consumed in ancient Egypt and Rome, Italians are credited as the people who invented pizza first. During the 1700s and 1800s, Naples was a bustling waterfront city, especially near the shore, where overcrowding and primarily outdoor living forced locals to find quick, easy ways to feed their families. Pizza became a common dish because of its limited ingredients and handy portability, but it was considered a street food for the poor, and unsuitable for the upper class.

Source: Salerno's Pizza