In Greek mythology, Sisyphus or Sisyphos (ˈsɪsᵻfəs; Ancient Greek: Σίσυφος Sísyphos) was the founder and king of Ephyra (now known as Corinth). Hades punished him for cheating death twice by forcing him to roll an immense boulder up a hill only for it to roll back down every time it neared the top, repeating this action for eternity. Through the classical influence on modern culture, tasks that are both laborious and futile are therefore described as Sisyphean (sɪsᵻˈfiːən).
R. S. P. Beekes has suggested a pre-Greek origin and a connection with the root of the word sophos (σοφός, "wise"). German mythographer Otto Gruppe thought that the name derived from sisys (σίσυς, "a goat's skin"), in reference to a rain-charm in which goats' skins were used.
Sisyphus was formerly a Thessalian prince as the son of King Aeolus of Aeolia and Enarete, daughter of Deimachus. He was the brother of Athamas, Salmoneus, Cretheus, Perieres, Deioneus, Magnes, Calyce, Canace, Alcyone, Pisidice and Perimede.
Sisyphus married the Pleiad Merope by whom he became the father of Ornytion (Porphyrion), Glaucus, Thersander and Almus. He was the grandfather of Bellerophon through Glaucus; and of Minyas, founder of Orchomenus, through Almus. Another account related that Minyas was Sisyphus's son instead.
In other versions of the myth, Sisyphus was the true father of Odysseus by Anticleia instead of Laërtes.Hyginus, Fabulae 201; Plutarch, Quaestiones Graecae 43; Suida, s.v. Sisyphus
Sisyphus was the founder and first king of Ephyra (supposedly the original name of Corinth). King Sisyphus promoted navigation and commerce but was avaricious and deceitful. He killed guests and travelers in his palace, a violation of guest-obligations, which fell under Zeus' domain, thus angering the god. He took pleasure in these killings because they allowed him to maintain his iron-fisted rule.
Sisyphus and his brother Salmoneus were known to hate each other, and Sisyphus consulted the Oracle of Delphi on just how to kill Salmoneus without incurring any severe consequences for himself.