Pausanias 3.5.1

When Pausanias fled, his sons Agesipolis and Cleombrotus were still quite boys, and Aristodemus, their nearest relative, was their guardian. This Aristodemus was in command of the Lacedaemonians when they won their success at Corinth.

When Agesipolis grew up and came to the throne, the first Peloponnesians against whom he waged war were the Argives. When he led his army from the territory of Tegea into that of Argos, the Argives sent a herald to make for them with Agesipolis a certain ancestral truce, which from ancient times had been an established custom between Dorians and Dorians. But Agesipolis did not make the truce with the herald, but advancing with his army proceeded to devastate the land. Then there was an earthquake, but not even so would Agesipolis consent to take away his forces. And yet more than any other Greeks were the Lacedaemonians (in this respect like the Athenians) frightened by signs from heaven.

By the time that he was encamping under the wall of Argos, the earthquakes were still occurring, some of the troops had actually been killed by lightning, and some moreover had been driven out of then senses by the thunder. In this circumstance he reluctantly withdrew from Argive territory, and began another campaign, attacking Olynthus. Victorious in the war, having captured most of the cities in Chalcidice, and hoping to capture Olynthus itself, he was suddenly attacked by a disease which ended in his death.2