Xerxes I (r.486-465 BC) was a Persian emperor most famous for the defeat of his massive invasion of Greece of 480-479 BC (Greco-Persian Wars). The Persian Empire had been entangled with the Greeks for almost its entire existence. The Empire was founded by Cyrus II the Great after he overthrew the last Median Emperor in 550 BC. In 547-546 BC Cyrus defeated the Kingdom of Lydia, in western Asia Minor. Lydia had ruled the Greek cities along the coast of Asia Minor (in particular the Ionian Greeks), and after defeating Lydia Cyrus had sent some of his generals west to take possession of these cities.
In 500 BC the Ionian Greeks revolted against Persian control. For several years they managed to maintain their independence, but they were finally defeated by Darius I in 494-3. Darius then turned his attention to the mainland Greeks, who had provided some support to the Ionians. Darius's invasion was turned back after defeat at Marathon in 490, and Darius began to prepare for a larger scale expedition.
These plans were disrupted by Darius's death in 486 BC, but for once the Persian succession went smoothly. Darius had married Atossa, the daughter of Cyrus the Great. Their son Xerxes had been born very soon after Darius had seized the throne in 521/2, and had thus been raised as a Royal prince. He had been introduced into government during his father's lifetime, and served as Governor of Babylon. He was chosen as heir during his father's life, despite the existence of an older brother, Artabazanes. Xerxes was thus an experienced ruler when he came to the throne in 486.
Xerxes was immediately faced with a crisis in Egypt, where a revolt had overthrown Persian power. He suppressed this revolt without great difficulty in 485, and then imposed a Persian form of government on the area, overthrowing the previous Persian habit of adapting the local systems. He was hugely unpopular in Egypt, which he treated as a conquered province and never visited.
This was followed by two revolts in Babylonia in 482 BC, each led by a pretender to the Babylonian throne. The second of these, led by Shamash-eriba, was put down by Xerxes's son-in-law Megabyzus. After taking Babylon Xerxes had the fortifications and temples destroyed and melted down the gold statue of Marduk.
Previous Persian rulers had called themselves King of the Persians, the Medes, Babylonia and Egypt. Xerxes now abandoned the later two titles, and kept Persia and Media.
Xerxes was now free to turn his attentions to Greece, encouraged by a party of Greek exiles at his court and by his brother-in-law Mardonius. Xerxes spent three years preparing for this expedition, and raised a massive army. Herodotus claimed that it was five million strong, although modern scholarship had reduced that figure to at most a tenth of that figure.
After spending the winter of 481-480 in the former Lydian capital of Sardis he led his armies across the Hellespont into Europe in 480. Two bridges of boats were built across the straits at Abydos. When one of them was destroyed in the storm Xerxes was said to have had the straits whipped, although this may be a Greek story designed to emphasis the tyrannical nature of his rule. The bridges were rebuilt and the army crossed the straits. Xerxes then advanced along the Greek coast, with the fleet advancing alongside the army and providing it with supplies. The building of the bridges was later portrayed as an act of hubris in the Greek tragedy the Persians, written by Aeschylus. The act of building the bridges was portrayed as having been an attempt to turn the sea into land, and Xerxes was punished for his hubris by the defeat on the sea at Salamis.
The Greeks famously attempted to stop the Persians at Thermopylae (August 480), but the Spartans and their Thespian allies were destroyed after the Persians found a route around their defensive position. The Greek fleet was forced to retreat from Artemisium by the defeat on land. Athens fell to the Persians, but the Athenians escaped. They then played a major part in the Greek naval victory of Salamis (29 September 480), which ended this first phase of the invasion. After this defeat Xerxes decided to return home, leaving his capable brother-in-law Mardonius in charge of the remaining troops in Thessaly.
This stage of the Greco-Persian War reached its conclusion in 479. Mardonius was killed at the battle of Plataea, and with him the heart went out of the Persian effort. Their fleet was defeated at Mycale on the coast of Asia Minor, and Thebes, one of the Greek cities to side with them, was captured. The Persians withdrew from mainland Greece, although they did retain a foothold in the north.
Xerxes remained on the throne for another decade and a half after the failure of his invasion of Greece, but he slowly withdrew from active government and spent most of his time in his three capital cities - Susa, Ecbatana and Persepolis. The war dragged on around the Aegean, where the Greek Delian League won some successes but slowly turned into the Athenian Empire. One of the last battles of Xerxes's reign was the naval battle of the Eurymedon River (466 BC) in which the League destroyed a Persian fleet.
The last years of his life aren't well documented. Xerxes spent much of his time at his courts, where he was responsible for a massive building programme. He finished his father's work at Persepolis, then built a palace of his own, and began work on the Hall of a Hundred Columns. This was finished during the reign of Artaxerxes I.
This period also some of the deadly court intrigues that plagued the later years of the Achaemenid dynasty. Amongst the plots was one in which Xerxes' queen convinced him to kill his brother's entire family.
Xerxes was assassinated in 465 BC by Artabanus, a senior member of his court. Two different accounts of the end of his reign have survived. In the first Artabanus killed Xerxes's son Darius and then killed the Emperor to avoid being punished. In the second he killed Xerxes, then convinced his younger son Artaxerxes that it had been Darius who committed the crime. Artaxerxes killed his brother in revenge. In both versions Artabanus ruled the Empire as the power behind Artaxerxes I for several months before being killed in hand-to-hand combat by him.
Xerxes was the last of the great Persian emperors of the Achaemenid dynasty. The Empire survived for another 135 years after his death, before falling to Alexander the Great, but many of the later Emperors were inactive or mediocre, and many of the Empire's successes were achieved by the satraps who ruled the provinces. Although other emperors suffered military setbacks (in particular in Egypt), it was Xerxes's retreat into his court that was perhaps the most significant, marking the point at which the Emperors began to go from being active rulers of the Empire to becoming increasingly the pawns of court factions.