The Worthy Cesanese

Why do regions and grapes go missing? Why do hilltop gems like Piglio in southern Lazio, with its indigenous grapes, almost vanish when even the smallest corners of the Piemonte and its nebbiolo remain exalted? While this was true for all of Lazio, as Diego and I continued an hour southeast of Rome to the province of Frosinone, knowing that cesanese is such a spectacular gem of a grape, the question seemed more pressing.