Romagna

Not to be confused with Lomagna or Romania.
Map of the communes of Romagna as of 2009 (RA = Province of Ravenna, FC = Province of Forlì-Cesena, RN = Province of Rimini, RSM = Republic of San Marino)
Map of Cesare Borgia's Duchy of Romagna
Cesare Borgia's domains mapped. Sources are in the image's description.

Romagna (Romagnol: Rumâgna) is an Italian historical region that approximately corresponds to the south-eastern portion of present-day Emilia-Romagna in northern Italy.