Soos (Ancient Greek: Σόος) was a fictional king of Sparta, created in the 4th century BC in order to harmonise the list of the two Spartan dynasties.
Various deeds were also attached to his reign, dated by ancient authors to the 11th century BC.
Soos is supposed to be the son of Procles, the alleged founder of the Eurypontid dynasty, one of the two royal family in Sparta (the other being the Agiads).
[citation needed] Plutarch wrote of a time that the Clitorians encircled the Spartans, preventing their access to water sources.
Soos made an agreement that he would return the lands he had conquered to them if him and all his men would be allowed water to drink.