Battle of Halys (585 BC)

Battle of the Eclipse
Part of Lydo-Median war
Halys River in the border regions of the Lydian and Median kingdoms in the early 6th century BC
Date May 28, 585 BC (supposedly) Location Halys River (modern Kızılırmak River, Turkey) (supposedly) Result Draw as the battle is interrupted by eclipse Peace agreement
Belligerents
Lydia	Media
Commanders and leaders
Alyattes	Cyaxares or Astyages

Draw as the battle is interrupted by eclipse

The Battle of the Eclipse or Battle of Halys was fought between the Medes and the Lydians in the early 6th century BC. The result was a draw which led to both parties negotiating a peace treaty and ending a six year war.

Herodotus writes that in the sixth year of the war, the Lydians under King Alyattes and the Medes under Cyaxares were engaged in an indecisive battle when suddenly day turned into night, leading to both parties halting the fighting and negotiating a peace agreement. Herodotus also mentions that the loss of daylight had been predicted by Thales of Miletus. He does not, however, mention the location of the battle.

Cicero mentions that Thales was the first man to successfully predict a solar eclipse during the reign of Astyages. He was the son and successor of Cyaxares and his reign began at the end of the war after Cyaxares' death.

Pliny the Elder mentions as well that Thales had predicted a solar eclipse during the reign of Alyattes.

If one reads the description by Herodotus of the event as a solar eclipse, then based on modern astronomical calculations it can be identified with the solar eclipse of May 28, 585 BC, hence yielding the exact date of the battle. For the location of the battle, some scholars assume the Halys River (today Kızılırmak River) as it was located in the border region between both kingdoms. As Isaac Asimov notes, this would be the earliest recorded eclipse the date of which was accurately determined in advance of its occurrence.

However, such a reading is for a variety of reasons rather problematic and hence disputed by various scholars. For examples, the known astronomical knowledge available of that time wasn't sufficient for Thales' prediction.

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