Even if the tradition tells us that the spaghetti carbonara recipe is from Rome, the origins of the dish are uncertain. Of course, that hypothesis is the most reliable.
Carbonara starts to be mentioned after the liberation of Rome in 1944 with bacon brought by Allied troops in the Roman markets. This explains why in carbonara, unlike other sauces such as amatriciana, bacon and pig cheek are often reported as equivalent ingredients by the book. Of course, if you ask people from Rome, they would tell you: «Carbonara with bacon instead of pig cheek is a blasphemy». In Lazio, they really love pig cheek, and in fact in amatriciana sauce, for example, pig cheek is a forced choice.
During the Second World War, the American soldiers who arrived in Italy gave to cooks the idea to combine ingredients such as eggs, pig cheek or bacon, and spaghetti. When Rome was freed, the food shortage forced creativity to find great solutions only with military rations. In this context, another masterpiece happened: spaghetti carbonara recipe.
Another hypothesis assigns the intention to the charcoal burners («carbonari» in dialects from the center of Italy) in Abruzzo, near L'Aquila. Craftsmen used to prepare it using ingredients that are easy to find and preserve. In fact, to make charcoal it was necessary to monitor it for a long time and therefore it was important to have the necessary supplies. In this case, carbonara would be the evolution of the dish called «cacio e ova» (cheese from sheep's milk and eggs, in the Abruzzo dialect), usually brought by craftsmen to their haversack and consumed with their hands. The pepper was already used in good quantity for the preservation of the bacon, fat or lard used in place of the oil, too expensive for the charcoal burners.
A last hypothesis would trace the origin of the recipe to Neapolitan cuisine. 1837 Ippolito Cavalcanti's theoretical-practical cuisine book describes as normal, in the preparation of some dishes, to use ingredients found in carbonara: a beaten egg, cheese and pepper added after cooking. It is a technique commonly used today in dishes such as pasta and peas, pasta with zucchini, egg-tied tripe and meat stew with peas.