The Great Rhetra was the constitutional rule traditionally associated with Apollo’s oracle at Delphi and Sparta’s political order.
The Great Rhetra is preserved in ancient accounts as an arrangement that organized Sparta’s institutions. It is connected with Lycurgus and with the establishment or confirmation of bodies including the kings, the council of elders, and the citizen assembly. The text is short and its meaning is disputed, particularly because later writers transmitted it in different contexts.
One important issue concerns the assembly’s role. Plutarch reports a later addition limiting attempts to distort or overturn the people’s decision, while modern historians debate how early the relevant provisions were and how literally the tradition should be read.
The Great Rhetra was not a complete written constitution in the modern sense. It was more likely a traditional constitutional pronouncement or formula that later Spartans and ancient authors used to explain the legitimacy of their institutions. Its association with Delphi gave the political system a sacred foundation.