The Battle of Salamis was a battle between an Alliance of Greek city-states and the Persian Empire in September in the straits between the mainland and Salamis, an island in the Saronic Gulf near Athens in 480 BC. It marked the high-point of the second Persian invasion of Greece which had begun in 480 BC.

Although heavily outnumbered, the Greek Allies were persuaded by the Athenian general Themistocles to bring the Persian fleet to battle again, in the hope that a victory would prevent naval operations against the Peloponessus. The Persian king Xerxes was also anxious for a decisive battle. As a result of subterfuge on the part of Themistocles, the Persian navy sailed into the Straits of Salamis and tried to block both entrances. In the cramped conditions of the Straits the great Persian numbers were an active hindrance, as ships struggled to manoeuvre and became disorganised. Seizing the opportunity, the Greek fleet formed in line and scored a decisive victory, sinking or capturing at least 300 Persian ships.

As a result Xerxes retreated to Asia with much of his army, leaving Mardonius to complete the conquest of Greece. However, the following year, the remainder of the Persian army was decisively beaten at the Battle of Plataea and the Persian navy at the Battle of Mycale. Afterwards the Persian made no more attempts to conquer the Greek mainland. These battles of Salamis and Plataea thus mark a turning point in the course of the Greco-Persian wars as a whole; from then onward, the Greek poleis would take the offensive. A number of historians believe that a Persian victory would have hamstrung the development of Ancient Greece, and by extension western civilization, and this has led them to claim that Salamis is one of the most significant battles in human history.

Details of the battle are generally sketchy, and no one involved would have had a view of the entire battlefield. Triremes were generally armed with a large ram at the front, with which it was possible to sink an enemy ship, or at least disable it by shearing off the banks of oars on one side. If the initial ramming was not successful, something similar to a land battle ensued. Both sides had marines on their ships for this eventuality; the Greeks with fully armed hoplites; the Persians probably with more lightly armed Iranian infantry.

Across the battlefield, as the first line of Persian ships was pushed back by the Greeks, they became fouled in the advancing second and third lines of their own ships. On the Greek left, the Persian admiral Ariabignes (a brother of Xerxes) was killed early in the battle; left disorganised and leaderless, the Phoenician squadrons appear to have been pushed back against the coast, many vessels running aground.[1] In the centre, a wedge of Greek ships pushed through the Persians lines, splitting the fleet in two.

Artemisia the queen of Halicarnassus, and commander of the Carian contingent, found herself pursued by the ship of Ameinias of Pallene. In her desire to escape, she attacked and rammed another Persian vessel, thereby convincing the Athenian captain that the ship was an ally; Ameinias accordingly abandoned the chase. However, Xerxes, looking on, thought that she had successfully attacked an Allied ship, and seeing the poor performance of his other captains commented that "My men have become women, and my women men".

The Persian fleet began to retreat towards Phalerum, but according to Herodotus, the Aeginetans ambushed them as they tried to leave the Straits. The remaining Persian ships limped back to the harbour of Phalerum and the shelter of the Persian army. The Athenian general Aristides then took a detachment of men across to Psyttaleia to slaughter the garrison that Xerxes had left there. The exact Persian casualties are not mentioned by Herodotus. However, he claims that the next year, the Persian fleet numbered 300 triremes. The number of losses then depends on the number of ships the Persian had to begin with; something in the range of 200–300 seems likely, based on the above estimates for the size of the Persian fleet. According to Herodotus, the Persians suffered many more casualties than the Greeks because most Persians did not know how to swim. Xerxes, sitting on Mount Aigaleos on his throne, witnessed the carnage. Some ship-wrecked Phoenician captains tried to blame the Ionians for cowardice before the end of the battle. Xerxes, in a foul mood, and having just witnessed an Ionian ship capture an Aeginetan ship, had the Phoenicians beheaded for slandering "more noble men".