Pausanias became king in 445 BC, when his father Pleistoanax was forced into exile because he made a peace settlement with Athens, which was deemed dishonourable in Sparta.
In 403 BC, Pausanias engineered the restoration of the Athenian democracy, which had been replaced by the regime of the Thirty Tyrants installed by Lysander after his victory.
His father was forced to go into exile after his first military campaign against Athens in 445 because he was accused of having taken a bribe from Pericles and offered him a lenient peace as a result.
[7] During his second reign, Pleistoanax was the leader of the Peace faction in Sparta, in favour of negotiating a settlement with Athens to end the Peloponnesian War (ongoing since 431).
Thanks to his naval victories against Athens in the Aegean Sea, Lysander built a network of friendships with puppet oligarchies and the Persian prince Cyrus, which even overshadowed the Spartan kings.
[11] Pausanias' first known command was in Autumn 405, when he led the main force of the Peloponnesian League to besiege Athens,[10] although Agis was already in Attica, at the head of the garrison of Decelea, a stronghold occupied by Sparta since 415.
[9] The Peloponnesian War ended the following year after Lysander negotiated the Athenian surrender, notably with Theramenes, and installed a pro-Spartan oligarchy, known as the Thirty Tyrants, as he had done in Athens' former allied cities when he captured them.
[13] This regime was rapidly challenged by the Athenian democratic resistance led by Thrasybulus, who captured the Piraeus harbour in 403; the Thirty then retreated to the city of Eleusis in western Attica.
Sparta initially made a loan of 100 talents to the Thirty (to hire mercenaries), while Lysander went to Eleusis and his brother Libys as navarch blockaded Piraeus.
[26] On his return to Sparta from Athens, Pausanias was prosecuted for betrayal before a supreme court made of the Gerousia (composed of 28 gerontes and the two kings) and the five ephors.
[32] Following his trial, Pausanias disappears from the sources until 396, probably because he disapproved Sparta's renewed imperialist policy conducted by the Eurypontids, Agis and his successor Agesilaus II, notably against Elis, Thessaly, and the expedition against the Persian Empire.
With levies from all of Sparta's allies except Corinth and Thebes, Pausanias invaded Eleia through Arcadia, taking the border fort of Lasion, winning over four communities in Acroreia, and seizing Pylus.
[34] Some authorities have been tempted to reject this entire sequence of events because the main source for the Elean war, Xenophon, narrates two campaigns instead of one and attributes the leadership of both to the other king, Agis.
Pausanias' text is lost, and its only mention in ancient sources comes from a corrupted passage in Strabo's Geographica, written in the time of Augustus.
[37] The main point of his pamphlet seems to have been a call for the abolition of the ephors, and returning to the ancestral constitution of Sparta designed by the legendary, or perhaps mythical, lawgiver Lycurgus.
Modern scholars suggest that Pausanias argued that the ephorate was not founded by Lycurgus, as it had hitherto been assumed by the Spartans, because Aristotle (384–322) in the Politics wrote that it was created by king Theopompus in the 8th century.