Argos and Nauplia refers to a Medieval Lordship in Morea or Achaia.

The de la Roche family held the duchy of Athens until 1308 when Walter of Brienne became duke. Walter hired the Catalan Company, a group of mercenaries led by Roger de Flor, to fight for the Duchy against the Byzantine successor states of Epirus and Nicaea, but in 1311 they overthrew Walter and took over the Duchy, making Catalan the official language and replacing the French and Byzantine-derived laws of the Principality of Achaea with the laws of Catalonia. Walter remained in possession of Argos and Nauplia where he was titled as Duke.

List of rulers:

• Walter I of Brienne (VI of Brienne and nominally II of Athens), son of Walter of Brienne , 1311-1356
• Guy of Enghien (grandson of Walter I) 1356-1377 titled duke of Athens
• Maria (daughter of Guy) 1377-1388, titled duchess of Athens
• Pietro Cornaro (married with Maria) 1377-1388
• Sold to Venice 1388

Lords (vassals of the previous, and after 1388 vassals of Venice):

• Sohier I c. 1350-1367
• Gualter I 1367-1381 Son of Sohier I
• Louis I 1381-1394 Brother of Sohier I
• Guiu 1394-?

To Mistra later than 1394