The Duchy of Reggio was one of the states that belonged to the Duchy of Modena and Reggio, ruled by the House of Este, in the north of Italy, in a territory now belonging to the Province of Reggio Emilia.
Reggio Emilia | Reggio Calabria | Grand Duchy of Lithuania | Duchy of Brabant | Duchy of Saxony | Duchy of Carinthia | Duchy of Burgundy | Duchy of Cornwall | Grand Duchy of Hesse | Grand Duchy of Mecklenburg-Schwerin | Reggio | Duchy of Parma | Chancellor of the Duchy of Lancaster | Duchy of Warsaw | Duchy of Prussia | Duchy of Jülich | Lorraine (duchy) | Grand Duchy of Baden | Duchy of Milan | Duchy of Mecklenburg-Schwerin | Duchy of Lancaster | Duchy of Holstein | Duchy of Savoy | Duchy of Nassau | Duchy of Limburg | Duchy of Württemberg | Duchy of Pomerania | Duchy of Luxembourg | Grand Duchy of Oldenburg | Duchy of Spoleto |