After more than a quarter century of warfare with their ancient rival Sparta, the whole of Greece became unified under Athenian leadership. The two city-states had often been at odds while carrying a begrudging respect for one another, particularly in their battles against Persian invasion. At Marathon in 490 BC, Athens defeated a Persian landing force in a downhill charge that annihilated the Persians before the Spartans could arrive. Ten years later, at Thermopylae, the Spartan Leonidas led an epic defense that stalled the Persian army while the Athenian general Themistocles destroyed the Persian fleet at Salamis. Further allied victories against Persia drove the empire back to Asia Minor.
The city-states grew in power, and their rivalry turned to all-out warfare. They traded victories and defeats until both sides were exhausted in 421 BC. Sparta and its allies had powerful land-based armies, conquering Attica, the region around Athens, time and again. Each siege lasted only a few weeks, however, as the Spartan army had to return to keep the helot slave population in check. Athens, meanwhile, maintained a vast empire of islands through its democratically supported navy. A peace treaty was proposed and signed by Spartan general-kings and Athenian politicians, led by the strategos (elected general) Nicias. Both sides vowed to uphold it for fifty years. It took less than seven years for the war to resume when Athens’s ally in faraway Sicily, Segesta, called for military aid against Syracusan attack.
The young Athenian leader Alcibiades championed the campaign to support them. Syracuse was the most powerful of the Greek colonies on Sicily, a land rich with grain and trade. If they conquered it, the Athenians could bring many other cities into their Delian League, perhaps enough to overwhelm Sparta. He had supporters such as enthusiastic Lamachus, but others opposed starting a new war, especially Nicias, who had prompted peace years before. In an energetic speech, Nicias outlined the vast resources Athens would have to expend to even attempt a conquest of wealthy, powerful Sicily. The speech backfired, invigorating the assembly into voting to send those soldiers and ships with hopes of seizing rich new colonies. Nicias himself was voted to be among the commanders, along with Alcibiades and Lamachus.
Just before the fleet sailed, hermai all over the city were desecrated. Marker stones dedicated to Hermes, god of luck and travel, were venerated in Athens as they not only had religious significance but also established boundaries, gave directions, and served as meeting places. Alcibiades and his cronies were blamed, primarily by Nicias and others who opposed the brash young Athenian. Alcibiades requested a trial to prove his innocence, but the request was denied.
Rather than wait and be recalled once his opponents who stayed behind to have the ear of the assembly, Alcibiades threw himself into his own trial. For hours, he debated with himself, waiting for his accusers to appear. His theatrics did gather a crowd, and eventually a quorum determined that he was innocent. His embarrassed political foes dropped the issue.
Upon arriving in Sicily, Alcibiades led the army, balancing Nicias’s conservatism with Lamachus’s eagerness to attack Syracuse head-on. The first battle in 415 BC proved a new stalemate as the Athenian infantry put the Syracusans to retreat, but the massive Syracusan cavalry kept the Athenians from pursuit. That winter, the Athenians completed a wall to siege the city, making cavalry ineffective, and Syracuse surrendered. Using the victory to his advantage, Alcibiades rapidly moved from city to city gaining allegiance from their Greek leaders, first in Sicily and then in southern Italy.
Within a few years of campaigning and diplomacy, the Athenian Empire had nearly doubled in size. Sparta’s position as leader of the oligarchies of Greece waned, and more city-states followed the Athenian model of populace-rule. Alcibiades masterminded a new war with Sparta, baiting them into an attack that was painted as imperialistic to the other Greeks. After the defeat and forced installation of democracy into Sparta, the first great threat to Athens came from the north as expansionistic Macedonians marched. Using the full weight of its empire, such as effective Sicilian cavalry, Athens countered the Macedonian assault and turned it into a client state.
In the coming century, Athens would face other incursions from growing powers. Romans from central Italy threatened allies in the south, requiring counterattacks again and again. Athens also faced rivalry in Sicily from growing Carthaginian influence, which prompted the outright conquest of the once-Phoenician colony. Persia continued its rule in the east, regularly fighting over cities in western Asia Minor with large Greek populations and losing Egypt after a rebellion with Athenian support. For centuries, Athens served as a political and intellectual capital of the world, attracting geniuses such as Archimedes and Hiro. Ultimately decadence caused the democratic Athenians to collapse, leaving a power vacuum in the Mediterranean that would last until Hunnish invasion.
In reality, Sparta won the Peloponnesian War. Alcibiades left without having a trial and was recalled immediately upon arrival. He fled out from under arrest and made his way to Sparta, where he served as a military adviser recommending reinforcement of Syracuse. The Athenian expedition to Sicily proved to be ruinous, devastating Athenian manpower and money just as Nicias had feared and ultimately leading to Spartan superiority in Greece. Alcibiades later returned to Athens, then to Persia, then back to Athens, and finally was slain in Thrace surrounded by mistresses. Spartan domination of Greece rapidly declined over the next decades, ended in conquest by Macedonian king Philip II, father of Alexander the Great.