Where does "pizza pie" originate?

The term pie might have been first used in New York where Italian immigrants had settled from the second half of the 19th century. My idea is that Americans rightly called it 'pie'. But since Italians told them its name was pizza, 'pizza pie' was a natural way to call it.

• Gennaro Lombardi entered the picture as the father of American pizza. - He first opened a grocery store in New York City in 1897 and it quickly became a popular lunch hangout after Gennaro began selling tomato and cheese pies to take out. Gennaro’s early pizzas were conveniently wrapped in plain paper and became a favorite of workers. Gennaro came up with the idea of offering to sell his pizzas by the slice.

from The Pie That Conquered America -The First Pizzeria in the United States

The following useful comment offers more insight:

• Yes, pizza pie is simply pizza. It used to be more common, but has gotten rarer over the decades, although you’ll still hear it, and the standalone pie is very common as the unit of pizza.

• The OED records pizza pie from 1939, which is also the first citation of pizza in a non-Italian (i.e., American) context

• There’s also tomato pie, which is another old name for a pizza, once common to New York, New Jersey, Connecticut, and Pennsylvania, and which DARE records from 1942. I recall a sign for “Maruca’s Tomato Pies” when I worked on the Seaside Heights, New Jersey boardwalk in the 1980s, but no one ever actually called them tomato pies.

Evidence of usage of the expression "pizza pie" can be found in an April 21, 1939 article by food columnist Clementine Paddleford of New York Herald Tribune :

• Largely, though, most Americans at that time had never heard of pizza. "If someone suggests a 'pizza pie' after the theater, don't think it is going to be a wedge of apple," wrote New York Herald Tribune food columnist Clementine Paddleford in 1939. "It is going to be the surprise of your life,... a nice stunt to surprise the visiting relatives, who will be heading East soon for the World's Fair. They come to be surprised, and pizza, pronounced 'peet-za,' will do the job brown."

I've heard it used, but still by far, it is not as common as simply "pizza". This Google n-gram specifically of American English, compares usage.

In a New-York Tribune article, printed December 06, 1903, the journalist clearly refers to the classic Italian dish. The piece is entitled: Do Fiery Foods Cause Fiery Natures? and tells us that Italian immigrants living in New York at the turn of the 20th century used to call it pomodori pizza (tomato pizza). Native New Yorkers saw its semblance to a pie and thus renamed it “tomato pie”.

In the article, the reporter misspells it as pomodore pizza, a forgiveable error, but it is worth noting that the dish did not contain any mozzarella, a cheese which would have been impossible to find in any New York grocery store in the late 1800s.

Take a lump of dough, and, under a roller, flatten it out until it is only an inch thick. On this scatter tomatoes and season plentifully with powdered red pepper. Then bake the compound.

Meanwhile, the American “green tomato pie”, and “ripe tomato pie”, both desserts, were well-known in the 19th century. It is therefore plausible that the more exotic term, pizza, was tagged onto “pie” at a later date to avoid any confusion.

The reporter also mentioned “salami pizza” and translated it as bologna pie. I don't know if “bologna” or “bologna sausage” used to stand for salami in the past, but today it is recognized as being the American name for mortadella.

Highly recommended: https://www.youtube.com/watch?v=v0eGUQWENMc , where you will find that "The Gaylords" (very famous in the fifties and sixties) use "pizza" and "pizza pie" indifferently. Italian pizza is simply a type of a pie, that's all. P.S.: I recommend also the other songs of that group.

My parents, who would be in their early 80s now and grew up in Yonkers on the Bronx city line never referred to pizza as pizza, it was always "hot pie"

Dad was Irish and mom was German. In the Yonkers groups on the net, many of us remember hearing hot pie in our youth.

Growing up in Bensonhurst, B'klyn, we always called a (or when ordering) a whole pie, "a pizza pie".

If you wanted a piece, it is called a "slice"

If you wanted a square, you called it "a Sicilian"...Which my favorite was from the center cut of the Sicilian pie...Which by the way, we never called it a Sicilian pie, it was refered to as a "whole sicilian"

Here's how the orders would go: "Frankie Boy, I'll have a slice please" "Two pies to go, thanks Vito" "I'll have a Sicilian from the center Joey, with a fountain Coke". "Give me two pies with pepperoni and a whole sicilian with extra cheese to go"

It's a New York thing