The Pyrrhike.

The most famous war dance in ancient Greece was the pyrrhike which became the national dance of Sparta, and persisted there long after Greece became a province of the Roman Empire and similar war dances had died out in other cities. The Greeks had several stories that accounted for the name of the pyrrhic dance. One said that it was invented by a Spartan called Pyrrhicus, though an alternative version claimed that Pyrrhicus was a Cretan. Another story connected the dance with the son of the hero Achilles, who bore two names: Pyrrhus as well as Neoptolemus. After Achilles was killed in battle at Troy, Pyrrhus came to Troy to take his father's place, and his greatest exploit was killing Eurypylus, leader of a force of Hittites that had come to help the Trojans. After he slew Eurypylus, he performed an exultant victory dance...