Interesting reading about Spaghetti Carbonara on The Epicurean blog.
The story of the origin of this dish and its place in cucina Romana is essentially contested. There are several competing theories, but most are anecdotal or food mythology.
First, although often thought of as a typical Roman dish, the name is said to come from a dish made in the Appenine mountains of the Abruzzo by woodcutters who made charcoal for fuel. They would cook the dish over a hardwood charcoal fire and use penne rather than spaghetti because it is easier to toss with the eggs and cheese.
Second, is more obvious , that given the meaning of “alla carbonara”, coal worker’s style, that the dish was a dish eaten by coal workers or that the abundant use of coarsely ground black pepper resembles coal flakes.