First Sacred War

Date	595–585 BC
Location	Mainland Greece
Result	Destruction of Kirrha and liberation of Delphi.

Belligerents

Amphictyonic League of Delphi,
Sicyon

Kirrha

Commanders and leaders

Cleisthenes of Sicyon

The First Sacred War or Cirraean war, was fought between the Amphictyonic League of Delphi and the city of Kirrha. In the beginning of the 6th century B.C. the attempt of the Pylaeo-Delphic Amphictyony, controlled by the Thessalians, to take hold of the Sacred Land (or Kirrhaean Plain) of Apollo ended up in this war. Its end was marked by the organization of the first Pythian Games. The conflict arose due to Kirrha's frequent robbery and mistreatment of pilgrims going to Delphi and their encroachments upon Delphic land. The war resulted in the defeat and destruction of Kirrha. The war is notable for the use of chemical warfare at the Siege of Kirrha, in the form of hellebore being used to poison the city's water supply.

The leader of the attack was the Tyrant Cleisthenes of Sicyon, who used his powerful navy to blockade the city's port before using an allied Amphictionic army to besiege Kirrha. The Athenians participated as well with a contingent led by Alcmaeon. On the Thessalian side, the leaders were Eurylohos and Hippias.What transpired after this is a matter of debate. The earliest, and therefore probably most reliable, account is that of the medical writer Thessalos. He wrote, in the 5th century BC, that the attackers discovered a secret water-pipe leading into the city after it was broken by a horse's hoof. An asclepiad named Nebros advised the allies to poison the water with hellebore. The hellebore soon rendered the defenders so weak with diarrhea that they were unable to continue resisting the assault. Kirrha was captured and the entire population was slaughtered. Nebros was considered an ancestor of Hippocrates, so this story has caused many to wonder whether it might not have been guilt over his ancestor's use of poison that drove Hippocrates to establish the Hippocratic Oath.

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