The Peloponnesian War by Donald Kagan [Book Summary – Review]

Around  590 BCE, two ancient civilizations, Athens and Sparta, crashed into each other. This war was different from any prior ones. In the past, huge armies organized and fought against one another in an open area. One opponent would be victorious, and the other would lose. 

The Peloponnesian War, however, was another story. The fighting ground for the most part was water, which enabled marine-based Athens to be advantageous. Yet, this fight was also one for the rebels, in which both sides got hurt by a number of revolts and upheavals. In other words, the ways wars were fought was shifted with this war in a way that is still relevant today.

In this summary, you will find out

  • how the war was turned into an inner conflict in a strange land;
  • how a disagreement that came from Sicily harmed the relative understanding between Athens and Sparta
  • who was it that operated in Athens, Sparta, and Persia?

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Chapter 1 – There was a burning antagonism between Sparta and Athens which led to the war.

It is crucial to know the historical background that lies within the animosity of these neighbors to perceive how the conflict between them turned into a long-lasting battle.

The Peloponnesian War is estimated to begin around 430 BCE. It had been thirty years since the Persian Wars ended, in which Athens and Sparta united their forces to fight Persia. After that, both regions were in relatively peaceful states.

Athens prospered and built a navy-based state. More than one hundred city-states in the Aegean Sea region, known as Delian League, were under Athens’ control. This union ensured the maintenance of commerce of various valuable goods. However, Sparta was not happy with this outcome. Sparta then created its own union, which was called the Peloponnesian League.

Even though Athens was able to maintain its regime rather smoothly, in Sparta, it was not like this because of their mixing of different ways of ruling.  In Sparta, there were two monarchs who chose judges called ephors and appointed sort of a parliament made up of thirty people. This group had the power to vote, but it could be only used when the aristocratic class in Sparta allowed doing so.

The social rules in Athens and Sparta also differed from each other. Whereas the people of Athens were all seen as equals, ordinary Spartans were divided into two hierarchical kinds; helots and periokoi. Helots stood one step above the slaves and they were farmers. The periokoi, however, were manufacturers and traders

Most importantly, in Sparta, the army was given the most value. And because of the two subordinate groups of people, other Spartans were allowed to prepare to join the military. However, as the number of helots was much higher than the Spartans, the possibility of helots rebelling always lingered, especially when the army advertised themselves. Thus, using their forces for any long war was not in Sparta’s best interest.

This statement was also true for Athens. Still, Sparta was really concerned about how dominant Athens and its alliance were turning out to be, in a way that might have made them uncontrollable. This concern came to its breaking point in 431 BCE.

Chapter 2 – What happened in Epidamnus caused the strife to worsen.

According to some experts, there are similarities between this war and World War I. Firstly, both of these wars were started by small incidents that took place in two unknown, secluded lands in the world. 

For The Peloponnesian War, this place was Epidamnus, a city located at the northest point of the coast of the Adriatic Sea. 5 years after the war first began, Epidamuns found itself in an inner state conflict. Some citizens asked for aid from the architects of the city in Corcyra. As they declined their request, the conflict became unmanageable.

There had been other times in which Athens and Sparta could face a conflict however it would be unpredictable to think that what had been happening in Epidamnus would cause such a war. Nevertheless, after Corcyra’s decline, Epidamnians went to Corinth.

Here it starts to become messy. The founders of Corcyra were from Corinth, but the current relationship between these states was combative. Then, Corinth was more than willing to aid a remote, obscure land Corcyra dismissed. There, Corinth founded a military post and also a new province.

Reasonably, Corcyra was unhappy with this, and it also had power too. After all, they had one of the relatively hugest fleets of the time. Corinth, however, did not possess the same power so they needed support which they would get from Sparta as a part of the Peloponnesian League.

At first, Sparta wasn’t keen on participating in this however as it seemed like Corcyra would get help from Athens, it got involved and attempts at arriving at a smooth resolution were made. But it was too late since Corinth had advanced too much to give up. They refused to end the fight mutually. They were officially at war. 

Yet, Corinth might have miscalculated Corcyra’s fortitude. Dozens of Corinthian navy were on their way to Corcyra. Corinth still did not give up. Instead of that, they were adamant to build an even bigger number of battleships. After Corcyra decided to pursue a union with Athens. 

Chapter 3 – With all the built-up tension, Athens and Sparta were approaching a huge conflict.

As the alliance between Athens and Corcyra was heard, Corinth also promptly made their way to Athens to make a case for themselves. By the September of 433 BCE, both parts were listened to by Athenian authorities.

Corinthians argued that as there was a peace agreement between them and Sparta, called Thirty Years’ Peace, it would not be wise for them to participate. Corcyreans, however, suggested that in the agreement an independent party’s union with Athens or Sparta was given permission. Thus, Athens was allowed to ally itself with Corcyra.

The Corinthians, who were full of rage, pointed out that if this was agreed upon, they would declare Athens as a foe.

Athens debated their choice for one more day. Then, they decided to fully ally themselves with Corcyra but only as a help in defense, which was unheard of in Greek tradition. They would not actively fight with Corinth, but if Corcyra needed it they would support them.

By doing this, the Athenians were focusing on dissuasion and not being aggressive. They wanted to prevent the strife to get worsen. The hope was also that Corcyra would be able to stand without needing any help. Indeed, after a while from the agreement in the Battle of Sybota, Athens was called for help as Corcyra was surrounded by Corinthians. However, as Athenian aid came into the battle, Corint drew back and went to their motherland.

During all these, the Peloponnesian League and Sparta were still not participating in this conflict as they did not wish to cause Corinth to rage on them. But this attitude didn’t stay the same. In a city in the Athenian League, which was built by Corinth, a rebellion began probably because of the Spartanians’ promise of helping them.

Megara also created an issue as a city that lies between Athens and Sparta. This city provided aid for Corinth for the Battle of Sybıta and was accused of trespassing in borders and hiding elusive captives. As a result, Megara was not allowed to use ports that belonged to Athens.

So, Megara rebelled against this ban. Two of the Peloponnesian league’s participants now had well-known issues with Athens. It was not possible for Sparta to not get involved anymore. In 432 BCE, a group of Spartans tuned in on these issues. Later they also heard from a diplomat from Athens. They had to make a choice.

Chapter 4 – As the attempts of staying out of conflict weren’t successful, the war started.

In the beginning, both Athens and Sparta possessed a powerful leader that could guide them. For Athens, this was Pericles, a hero of the Persian War whose ancestors founded Athens. He was a loved and assertive person and was renowned in Greek politics. For Sparta, this person was Archidamus, who not only was one of Sparta’s monarchs, but also a comrade of Pericles.

Both of these men were determined to protect the long period of peace. They agreed that winning this war would be hard on both parties. Moreover, Archidamus was very foresighted. Following their meetings in July, he was sure that had a war actually took place, it would end after such a long time that they would not see it while they were alive.

In spite of this warning, many Spartans feared that Athens’ moves were turning unruly. They thought that Athens was turning this situation to its advantage. They believed that Sparta had no choice but to come together with their alliances.

Sparta, in the beginning, declared formal displeasure with Athens as they were sneakily getting ready for the battle. After that, there was a time span that was filled with tension between the two states. Several times, Sparta offered Athens final proposals that would allegedly avoid any further conflict. There was a time where the offer supposedly suggested that it would free Greek. What it actually suggested was, however, demolishing Athens. What was also suggested most of all was lifting the Megarian Decree.

For the majority of Athens, this offer seemed doable to prevent a war. However, Pericles convincingly disagreed with Sparta’s wishes. More importantly, Pericles needed Sparta to act according to the Thirty Years’ Peace agreement, in which it was said that a conflict would end with compromise. That was why he did not agree with Sparta’s proposal. There was also no doubt in his mind that agreeing to this would only make Sparta want more from them.

It can be said that what Pericles suggested was true. One of Sparta’s biggest worries was Corinth’s warnings to them to depart from Sparta if they were not helpful, and their current order would not satisfy Corinth. 

Finally, Sparta shied away from compromising, although it was in the agreement, and Athens did not agree to any of their demands. Then, war emerged when Athens was attacked in the spring of 431 BCE by Thebans, a friend of Sparta.

Chapter 5 – Athens’ strategies, which were defense-based, didn’t play out like they thought they would.

As the war was decided on, Athens used an unconventional tactic. The plan, which was made by Pericles, was to defend their lands in a way that would show their great strength to Sparta. In short, Athens would use the bulwarks that surrounded the citadel as well as their higher-level navy to protect themselves from the attacks.

Pericles was aware of the Spartan military’s power on land as well as how Sparta thought that this would conventionally make them advantageous in a war, but this one would not be like other wars. Athens was planning on attacking with their navy, and according to Pericles, Sparta would soon know they were bound to lose. Surprisingly, both sides were wrong.

In the beginning, Pericles’ tactics were somehow working. The Spartans surrounded them however Athens’ defensive forces were enough to keep them in their place until their wills were broken.

In fact, Athens was even able to get possession of a number of small areas that were key points in the Peloponnesian League. However, at the end of the year, the reality was not so good. Athens didn’t make any harmful impact on Sparta whereas they were demolishing many valuable things in the areas they occupied.

Next year, Pericles knew the necessity to use more aggression. But there were also other problems in Athens as the city became deeply affected by a plague. It cost the city one-third of its citizens. On top of this, their navies started to prove to be too costly for them to manage. There was an urgent need to find a better strategy from Pericles’ one.

It would be found not long after. Pericles lost his life in 434 BCE. There seemed to be no one that could step in his shoes. However, two fellows named Nicias and Cleon came up with two alternative tactics. Nicias was in favor of ending the conflict as soon as possible while Cleon insisted upon his rejection of a settlement, and was aiming for a total win of the war. Yet, with both these paths, Pericles’ defense tactics were gone.

Chapter 6 – The war was vicious however following an important win of Athens there came a time of truce.

The practice of war was no longer two opposite sides fighting in a wide area. The Peloponnesian War didn’t follow this practice. Civilians were also invited to fight in many Spartan regions

The conventional ways of participating in war were completely changed. The practice of imprisonment, for instance, was a practice that changed. Then men of these war imprisoners were killed, and the women were enslaved. However, this wasn’t even the biggest inhumane practice of the war.

In many places, catastrophe surrounded everywhere as the war raged on. Everything was unstable, and the people of these towns started uprisings against Sparta or Athens for protection.

In 427 BCE, an uprising against Athens began in Mytilene and it ended with the killing of around one thousand men who were seen as more liable. In fact, Cleon at the start wished for all participants of the rebellion to be killed. This was showing mercy, but those did not always conclude smoothly.

After a long time, the faith in conciliation was restored with the brilliance Athenian general Demosthenes showed. In 425 BCE, he came up with the idea of building a settlement in Pylos, Messenia, which was a key place in warfare. He thought that this base could have been used for Athens to make strikes against Sparta.

This plan resulted in a glorious win for Demosthenes and Athens. The Spartan navy was demolished with this passage and 292 Spartan prisoners were taken, which included roughly 180 aristocrat Spartans. A cease-fire was called upon immediately, which was a first in the period of the war.

Initially, Athens was hoping to turn this small win into a total one. But the odds weren’t with them as they lost Amphipolis, an area that had scarce goods of Athens, to Sparta. As they tried to make up for what they lost, Cleon, the primary supporter of the war in Athens, died at war. This caused a truce to become a more popular opinion. Thus, in March 421 BCE, the “Peace of Nicias” was authorized.

Chapter 7 – The agreement lasted five full years, but a debacle in Sicily caused it to be broken.

As Spartan prisoners were used for negotiations, Athens and Sparta were able to come to an agreement. Both of the sides were not able to actually reach an absolute win during the war. Yet, although a cease-fire was put in place, they were not on exactly friendly terms.

This was particularly true for allies like Thrace, who was not giving up on Amphipolis, although this city was an important fragment of the agreement. So, the fact that this agreement was probably not going to be permanent was somehow out there.

Argos, a city located between Corinth and Sparta, was among the places that were threatening. Following the establishment of the agreement, Argos started to build an Argive League, an alliance that departed from the Peloponnesian League. This league quickly started collecting members.

As a result, the Battle of Mantinea was fought, which ended with Spartan victory. During this conflict, the signs of a new conflict began appearing to be smoothly concluding, following Hyperbolus’ leadership. He would later be outcasted from Athens. However, what led Sparta and Athens back to fighting each other was what was happening in Sicily.

These events are often compared to the American presence in Vietnam. In 416 BCE, Athens was asked for help by Segesta and Leontini, two associates in Sicily. Leontini was about to be invaded by another city in Sicily, Syracuse. But, similar to Vietnam, this helping plan started clumsily and got worse as Athens became more attached to it.

Yet, it can be suggested Nicias was trying to be accountable in his choices although they might not have turned out as they were planned. Right from the start, Nicias was against helping Sicily, and he tried to pursue others too. The majority did not listen to him, but still, let him lead them.

In the first task force that was launched, there was a lack of horse soldiers, which suggests that Nicias was still hopeful in avoiding conflict. Consequently, Athens missed the chance for an initial win as they began their fight with the Syracusians.

So, this allowed the Syracusians to ask for help from Sparta in the meantime, which resulted in thousands of captive Athenians being killed and for Athens to lose horrifically.

Chapter 8 – As Persia supported Sparta, Athens’ regime was at gunpoint.

As Sparta and Athens again clashed in Sicily, this meant the time of peace was long gone. Attempts at preventing rebellions were again at work, and they were once again making and losing allies.

Persia entered the game following Sicily. As a prior foe of Athens and Sparta, Persia stood neutral for a long time. However, after Athens’ big defeat in Sicily where it lost respected leaders, Persian monarch Cyrus started to invest in Sparta by offering help in building fleets.

Previously, the draw of Persian allyship was important to some Athenians. Indeed, a contributing factor in a stunt that aimed to abolish the Athenian government was also this.

Alcibiades, an Athenian general, also took part in this overthrow. Known as a charming figure, he had also raced at the Olympics. He was very clever and had been a general of the public’s own choosing several times.

Moreover, he also went to Sicily with Nicias as a general. However, on their way there, he had a real change of heart. To escape from the possibility of execution, he ran away to Sparta. Then, he got the role of an advisor of Tissaphernes, a Persian viceroy.

After Alcibiades planted the seed for the suggestion of the Persian alliance with Athens, if Athens became an oligarchy, all was set for a governmental overthrow. And when it was obvious that Alcibiades was not completely honest about the info he provided, the boat was already missed.

An assembly called Four Hundred became in charge in Athens, pretending to be only actualizing small changes to the Athenian democracy. There was a financial need to go on with the war however making this kind of functional betterment was of no interest to the Four Hundred.

After a short while, it was heard that this group was prepared to sacrifice Athens to ensure stability. Allegedly, the Spartan navy was on its way to Athens which led to a rebellion, the overthrowers were indicted for treason. One of them managed to run away, but the rest were killed.

Surprisingly, as the democratic rule was welcomed again, the public wanted a charming, but the problematic leader who was none other than Alcibiades.

Chapter 9 – Following shameful losses, Athens was able to reach success for the last time before things got ruined.

What Athens needed was some heroism. That is why they resorted to Alcibiades who had ambition and courage in him. They were not aware of how involved he was with the recent political situations, and, to be fair, Alcibiades probably still had a loyalty to Athens. That is why before he came back to Athens, he wished to give its people the gift of a win. He was also worried that some may not be really welcoming towards him.

And, as he was welcomed back in 407 BCE, he brought successful wins in the Hellespont region with him by getting Selymbria and winning back Byzantium.

However, his stay didn’t last long. With a fleet, he went to go up against the Spartan leader Lysander to Ephesus. Lysander did not take to bait an on-water fight and Alcibiades left the warships to Antiochus, as he went to see a general, which was a huge misstep.

When Alcibiades went away for a while, Antiochus tried to fight with Lysander on his own, which ended in a dreadful loss. Alcibiades shamefully made his way to Gallipoli.

But  Athens would be triumphant over the Spartans one more time. By using unconventional ways of warfare, a group of Athens managed to win over Sparta at the Battle of Arginusae. A considerable part of the Spartan fleet was abolished, but the way too chaotic functioning of the Athenian navy caused many sailors to die cast a shadow on Athens’ win. 

Meanwhile, in Athens, an election was made, and the execution of eight navy generals who took part in this battle was approved. This would be lamented by most of the people of Athens down the road as it also caused the city to be sorrowful of this loss. 

The issues Athens faced became even more complicated with Persia funding Sparta. Because of this, Sparta was able to recover from a fight faster than Athens. Now, all was set for one last face-off in Aegospotami.

Chapter 10 – Athens was not the victor in the end however the state kept its democracy going strong.

Back in Aegospotami, Lysander was once again the leading guide of the Spartan navy. He was greatly admired by the Spartan monarch Cyrus, and he strategically decided the fight to be located in Aegospotami. Because this region had no ports, Athens would not have the advantage of using their great fleets according to Lysander.

Once more, Athens was unable to move and bait Lysander. Shockingly, Alcibiades arrived and attempted to guide some unpracticed Athenian soldiers. He probably had considered these issues in Gallipoli. He suggested the navy retreat and go to a close headquarters until Lysander was out. At that moment, Athens was landing their fleet and also was short of necessary materials for survival. It is a mystery what would happen to them had they listened to Alcibiades.

Alcibiades also thought that he could lure Lysander out by attacking the Athenians with some Thracian troops. This suggestion, like his many others, was not the entire truth however that was unimportant. There wasn’t anybody who would take action in accordance with Alcibiades’ claim after he lost his reputation. Instead, the strategy was for thirty warships to make their way to Lysander to get him to go into a clash.

There were some who were not prepared for this decision. This attempt was not successful even if it was meant to be a calculated tactic. Lysander was able to capture the thirty ships and other remains of the Athenian navy were already landed. A small number of Athenian ships were unharmed in the navy and thousands of Athenian sailors were murdered. For Athens, the war was over. 

Cities that showed allyship to Athens were quickly informed that if they offered any help to Athens, it would be their end. Sparta’s intention was to make Athens yield. In the beginning, Sparta did not agree to anything other than the total extermination of Athens. Sparta’s wish was for Athens to completely collapse as a state, but Athens was not about to.

After a while, the bearer of good news was Theramenes, one of the influential figures of the Four Hundred. Following a dreadful period of agreement attempts between Athens and Sparta, with the guidance of Theramenes, Athens was granted an avoidance of total collapse if the city took down its bulwarks, gave back what remains of their navy, and turned into an oligarchic rule.

As they thought this was the best possible outcome, Athens complied. Impressively, this allowed them to live on. An ex-leader, Thrasybulus, managed to run away and set up a small troop outside of Athens. Ultimately, because of his labor, the one who was against Athens’ democratic rule was fought off. There were very few who were severely given penalties this time. The period of absolution, serenity, and control finally had arrived. All in all, everything that was needed for the Second Athenian Empire to thrive was in readiness.

The Peloponnesian War by Donald Kagan Book Summary – Review

The Peloponnesian War lasted thirty years and featured Athens and Sparta as well as the alliances they made. It caused states that existed in the same Greek region to antagonize one another in a collision that was unheard of before in many ways. Athens tried to defend itself by making use of its superior navy, but it could not resist Sparta for long, with the help it got from Persia towards the end. With the financial advantage and the strength Sparta had, it was able to gain victory in this war. As for Athens, it would soon begin to restore its realm with its dedication to the democratic way of ruling.

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