|Roman Invasion of Achaea
Principia Moderni III
Hospitaller troops storming the fortress of Arkadia.
| Roman Empire||Principality of Achaea|
|Commanders and leaders|
| John VIII Palaiologos ||Prince Centurione II Zaccharia (POW)|
The Roman Invasion of Achaea was a military conflicted that involved the Roman Empire and its ally the Order of the Knights Hospitaller against the Principality of Achaea, the last independent state in Greece not bound to either the Romans or the Venetians and the last claimant to the Latin Empire.
Roman forces were eager to recapture this region as it meant the near total unification of southern Greece under their control as well an end to any rival claims to the Roman state. For the Achaeans, the war meant a survival of Latin rule in Greece and the possibility of pushing into other former Latin areas like Boetia or Attica.
The Knights of Hospitaller, while technically friendly with the Achaeans, also participated in military activities to aid their ally the Romans. Grandmaster Vittorio De Luca, related to the Roman Imperial family by marriage, hoped to see the Romans become a powerful state to oppose the rising Ottomans, and had previously helped the Romans in the Second Cypriot War.
With Achaea as the final target of Latin rule in Greece, Roman forces marched upon the capital of Patras after defeating the Latins at Chalandritsa. Patras was captured after a lengthy siege, and as was the custom, the last ruler of the Principality, Centurione II, was taken prisoner, sharing the fates of the kings of Cyprus.Meanwhile, Hospitaller forces raided the coast of Elis and attacked Achaean castles there, establishing a foothold in Greece for the order. This caused concern as some Roman nobles considered this to be trading one Latin state for another. However, Hospitaller rule in the area lasted less than a year, as the Hospitaller order had become bankrupt by its conquests and as a result downsized, selling or gifting most of its land to the Romans.