Amatriciana comes from Amatrice, a town in Lazio. Its origin is divided between Lazio and Abruzzo, since Amatrice belonged to the latter until 1927.Some say that is the “red” version (with tomato sauce) of gricia; others say gricia is the “white” version (no tomato sauce) of amatriciana. 

Whatever its origin is, that is as delicious as...try to end this sentence!