I am sure most of us are aware about the Greco-Persian wars that have been retold in the popular movie 300, where Leonidas and his brave 300 make their last stand at Thermopylae (August 480 BCE) against the Persian army commandeered by Xerxes, followed with the Greek’s naval battle against the Persian navy in the battle of Salamis (September 480 BCE), as the main point of the second 300 film. Yet, not shown in the two 300 movies are the events that occurred after the battle of Salamis, and is key to ending the Greco-Persian war, when after a series of political negotiations it became clear that the Persians would not gain victory through diplomacy and the two armies met at Plataea in August 749 BCE. The Greeks, fielding the largest hoplite army ever seen, won the battle and finally sent Xerxes packing and ended his ambitions in Greece.
The victory against Persia ends a chapter and opens a new one, with the threat of Persia diminished, Greek continued its inter-city rivalries, and unsurprisingly two of the most powerful city states are Sparta and Athens. Over the next several years, however, Spartan leadership bred resentment among the Greek naval powers that took the lead in carrying the war against Persian territories in Asia and the Aegean, and after 478 BC the Spartans abandoned their leadership of this campaign Sparta grew wary of Athens’ strength after they had fought alongside each other to disperse the Persian from their lands. When Athens started to rebuild its walls and the strength of its naval power Sparta and its allies began to fear that Athens was becoming too powerful. Different policies made it difficult for Athens and Sparta to avoid going to war, since Athens wanted to expand its territory and Sparta wanted to dismantle Athens's democratic regime.
The continuous piling of “mismatches” between Athenians and Spartans is stated to be one of the major factors leading up to the First Peloponnesian War, occurred during the years 460 – 445 BCE between the Delian League, headed by the Athens against the Peloponnesian League, led by Sparta. Sparta, although at first largely inept and is only involving Spartan soldiers in small skirmishes at first, took the first major step when war had broken out between Athens' ally Phocis and Doris, across the Corinthian Gulf from the Peloponnese. Doris was traditionally identified as the homeland of the Dorians, and the Spartans, being Dorians, had a longstanding alliance with that state. Accordingly, a Spartan army under the command of the general Nicomedes, acting as deputy for the underage king Pleistonax, was dispatched across the Corinthian Gulf to assist. The Athenians, after hearing wind of the Spartan army stationed in Boeotia, marched out with as many troops as the could muster to challenge the Peloponnesian League, the two armies met at the battle of Tanagra, where, after suffering with heavy casualties for both sides, a victory was gained by Sparta. The Athenians rebounded well after their defeat at Tanagra, by sending an army under Myronides to attack Boeotia. The Boeotian army gave battle to the Athenians at Oenophyta, but the Athenians ultimately scored the victory, leading to the Athenians conquering all of Boeotia except for Thebes, as well as Phocis and Locris. After their successful conquest, the Athenians pulled down Tanagra's fortifications and took the hundred richest citizens of Locris and made them hostages. Whilst also being able to finish the construction of the wall whilst all of the events are in progress.
Athens string of military successes suddenly came to a halt in 454 BCE, when its Egyptian expedition was defeated handily by the Persian army under Megabazus that had been sent overland against the rebels in Egypt some time earlier, and upon its arrival had quickly routed the rebel forces. The Greek contingent had been besieged around the Nile. The conclusion of the siege that took 18 months is the success by the Persian army of, destroying the Greek force almost entirely. Though the force thus obliterated was probably not as large as the 200 ships that had originally been sent, it was at least 40 ships with their full complements, a significant number of men.
The results after its loss in Egypt causes Athens to negotiate a peace truce with Sparta for 5 years, and focuses the next several years to concentrate its effort exclusively in the Aegean. This is the start of the end of the first Peloponnesian War. Athens and Sparta would go once again in the second Peloponnesian War, and I am sure this and the next war is giving us ideas for future franchises of 300.