The Spartan Diarchy: Monarchy in the Ancient World

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Ancient Sparta was, and still is, principally famed for its distinct warrior culture, the values of which are aptly exemplified by the almost legendary Battle of Thermopylae. Fought in 480 BC between 300,000 Persians under Xerxes I and 6,000 Greeks led by King Leonidas of Sparta, the involvement of 300 Spartan hoplites in the battle has been immortalised today in the form of films and fiction. The reality is no less impressive – the Spartan soldiers, despite being surrounded and heavily outnumbered, refused to retreat and killed 20,000 Persians before themselves being annihilated in a heroic last stand. Unique societies breed unique men. The extraordinary calibre of these hoplites can be seen in even better light in the context of their unusual yet successful political structure: the Spartan diarchy.

At the time of Thermopylae, Leonidas was not the only king of Sparta. Two kings from two different dynasties were sitting on the throne at once, the other being Leotychidas II. With two kings on the throne simultaneously, the Spartan diarchy is undoubtedly one of the most unique forms of rule to date, yet its success over the years remains undecided.

The origin of this diarchy is highly debated and exceedingly difficult to verify, but the most plausible story is that it was formed when smaller settlements merged into one, and the rulers of the two strongest settlements mutually agreed to share power when they merged.

The mythological interpretation of the genesis of the diarchy purports that it was concieved around 1100 BC with the post-Trojan War invasion of Lakedaimon by the Dorians (a warrior Greek tribe of the north) in which they overran the cities of the Peloponnese. These Dorians were ruled by exiled princes who claimed to be descendants of Herakles himself: brothers Kresphontes and Temenos, and Aristodemus, and Aristodemus’s twin sons: Eurysthenes and Prokles. Most of the Peloponnese was divided between them when their invasion was complete. The North East went to Temenos, Messenia went to Kresphontes, and Lakonia went to either Eurysthenes and Prokles or to their father, Aristodemos. This dispute of whether Aristodemos was alive for the Dorian invasion is where this myth is introduced.

The Lakedaimonians would have decreed that Aristodemus led them to their land and not his twin sons. However, following Aristodemus’s death, the Lakedaimonians wished to make his eldest son king, as was their custom. However, the two sons of Aristodemus were twins, thus they did not know which was the eldest. When they asked their mother, she lied, claiming she didn’t know which one was older, since she wanted both to become kings.

The Lakedaimonians then consulted the oracle of Delphi, which advised them to make both sons king, but to give more privileges to the elder one, still failing to solve their main issue. Finally, a mysterious man from Messenia told the Lakedaimonians to watch the mother of the twins in order to see which child she fed and washed first. If this order was random, then she was telling the truth, and genuinely did not know which child was born first, but if she consistently fed and washed one before the other, then this was the older twin. The mother who, unaware, therefore fed and washed the older twin first, who was revealed to be Eurysthenes.

Therefore, one king of Ancient Sparta was descended from Eurysthenes, and the other from Prokles, with the line of Eurysthenes being more senior, but with both having equal power in principle. The dynasties were named the Agiads after Eurysthenes’s son, and the Eurypontids after Prokles’s grandson.

Sparta was an oligarchy, ruled by few, though with some elements of democracy. For example, all male citizens had an equal vote in the Ekklesia – the citizens’ assembly. This council voted on the selection of the Gerousia, the council of elders, who were 28 citizens over the age of 60, elected for life. The two kings were also part of this council, making the total 30. Additionally, the council voted on the selection of the most powerful individuals of Sparta, the Ephors, who were five people elected from the whole population for a one year term. These councils also decided civil and criminal cases.

The kings did not have absolute power, instead operating in such a way that one person, be it a king or an Ephor, could not gain excessive power. They were, at first, judicial, military and religious figures. The kings were the chief priests of the state, maintaining communication with the oracle of Delphi, whose judgements had great power in Spartan politics, as evidenced by the story of the origin of the diarchy.

Aristotle described the kingship at Sparta as “a kind of unlimited and perpetual generalship”, since another important role they played was leading the military. Kings initially had the right to declare war and would lead military expeditions, an example being Leonidas’s leadership at Thermopylae. However, it was not permitted for both the kings to lead an army at the same time, as one always had to remain in Sparta to prevent the perpetual danger of a slave uprising from the helots.

Therefore, perhaps it is true to say that this diarchal political system was perfect for Ancient Sparta, allowing for military expeditions to display their strength abroad and expand, while still being able to prevent incessant civil unrest and uprisings back at home.

Over time, the power of the kings diminished and the power of the Ephors grew. Following the Persian Wars, the kings lost their right to declare war and had to be accompanied in the battlefield by two Ephors. Other than their role as generals in military campaigns, kings became mere religious figureheads, and effectively all political and judiciary power was channelled to the Ephors and the Gerousia.

Eventually, the diarchy and the power of Sparta broke down. This began after the liberation of Thebes and, more significantly, after their catastrophic defeat at Leuctra in 371 BC. Despite this decisive defeat, the Spartans managed to maintain their autonomy through the aid of tyrants, such as Dionysius I of Syracuse, and through mercenaries. In 331 BC, the Spartan King, Agis III, led an attempted revolt against the Macedonian hegemony over Greece and was defeated at Megapolis by Antipater, regent of Alexander the Great.

The end of the diarchy finally came about under the rule of King Kleomenes of the Agiad dynasty. Kleomenes sacked the Theban Megapolis in 223 BC and garnered further support by liberating some of the enslaved helots and giving citizenship to the perioeci (second-class citizens). He then set about killing all of  his opposition, including the Ephors. Finally, Kleomenes ended the dynastic diarchy by placing his brother Euclidas on the Eurypontid throne.

However, when Kleomenes was defeated by Antigonus III of Macedon in 222 BC just north of Sparta, his reforms were annulled and reversed. Once again, the diarchy returned, with the Agiad Agesipolis III, and the Eurypontid Lykurgus being placed on the throne. However, in 215 BC, Lykurgus deposed Agesipolis and proceeded to rule alone.

When Lykurgus died in 210 BC, his son, Pelops, was not yet a year old, resulting in Makanidas, a person of unknown descent, ascending to regency and ruling as tyrant. Following yet another Spartan defeat at Mantinea in 207 BC (where reportedly 4,000 Spartans died) to the Achaean League, another despot named Nabis came to power. Nabis tortured and exiled his Spartan opposition, and assassinated the 11-year-old Pelops, but was betrayed and assassinated himself by the Aetolian League (rivals of the Achaean League) 15 years into his rule.

Following this coup, the Aetolian League attempted to capture Sparta, but was repelled by an uprising of the citizens. Eventually, the Achaean League mustered an army under Philopoemen and persuaded the Spartan citizens to join them, defeating and murdering Nabis, the last king of independent Sparta.

The incredible history of the fascinating diarchy of Sparta ran through the Archaic period, the Persian wars and the Peloponnesian war, until it devolved into a monarchy under a series of tyrants from 222 BC. That the Spartan state retained its independence following the catastrophic defeat at Leuctra in 371 BC, and somehow afforded a few more crushing defeats at Megapolis and Mantinea, is yet another example of the perplexing and characteristic obstinacy of the Spartan state to admit defeat, for which they are so justifiably renowned.

Many would argue that the longevity of the ancient Spartan diarchy is a testament to the ingenuity of the political system of Ancient Sparta: a mad mix of monarchy, aristocracy and democracy. However, there was clearly a method to this madness, exemplified by the long-lasting yet unchanging nature of the diarchal system. Thus, while the Ancient Spartans are be renowned for their immortalised military campaigns, their impressive political innovation is perhaps too often understated.

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Herodotus. The Histories.

Aristotle. Politics.

Huse, J. (2016). The Dual Monarchy of Sparta. Classical Wisdom.