Pausanias (Greek: Παυσανίας; died c. 470 BC) was a Spartan of the 5th century BC. He was a scion of the royal house of the Agiads but was not in the direct line of succession: he was the son of Cleombrotus and nephew of Leonidas I, and served as regent after the latter's death, since Leonidas' son Pleistarchus was under age. Pausanias was also the father of Pleistoanax, who later became king, and Cleomenes. Pausanias was responsible for the Greek victory over Mardonius and the Persians at the Battle of Plataea in 479 BC, and was the leader of the Hellenic League created to resist Persian aggression during the Greco-Persian Wars.
After the Greek victories at Plataea and the Battle of Mycale, the Spartans lost interest in liberating the Greek cities of Asia Minor. However, when it became clear that Athens would dominate the Hellenic League in Sparta's absence, Sparta sent Pausanias back to command the League's military.
In 478 BC Pausanias was suspected of conspiring with the Persians and was recalled to Sparta; however he was acquitted and then left Sparta of his own accord, taking a trireme from the town of Hermione. After capturing Byzantium, Pausanias was alleged to have released some of the prisoners of war who were friends and relations of the king of Persia. However, Pausanias argued that the prisoners had escaped. He sent a letter via Gongylus of Eretria to King Xerxes (son of Darius), saying that he wished to help him and bring Sparta and the rest of Greece under Persian control. In return, he wished to marry the king's daughter. After Xerxes replied agreeing to his plans, Pausanias started to adopt Persian customs and dress like a Persian aristocrat.
Many Spartan allies joined the Athenian side because of Pausanias' arrogance and high-handedness. The Spartans recalled him once again, and Pausanias fled to Kolonai in the Troad before returning to Sparta as he did not wish to be suspected of Persian sympathies. On his arrival in Sparta, the ephors had him imprisoned, but he was later released. Nobody had enough evidence to convict him of disloyalty, even though some helots gave evidence that he had offered certain helots their freedom if they joined him in revolt. However one of the messengers that Pausanias had been using to communicate with Xerxes to betray the Greeks provided written evidence (a letter stating Pausanias' intentions) to the Spartan ephors that they needed to formally prosecute Pausanias.
The ephors planned to arrest Pausanias in the street, but he was warned of their plans and escaped to the temple of Athena of the Brazen House. The ephors walled up the doors, put sentries outside and proceeded to starve him out. When Pausanias was on the brink of death by starvation they carried him out, and he died soon afterwards. Thus Pausanias did not die within the sanctuary of the temple, which would have been an act of ritual pollution.
- Thucydides I,133 s:History of the Peloponnesian War/Book 1#Second Congress at Lacedaemon - Preparations for War and Diplomatic Skirmishes - Cylon - Pausanias - Themistocles