1. A son of Lycaon, and the reputed founder of Oresthasium, which is said afterwards to have been called Oresteium, from Orestes. (Paus. viii. 3. § 1; Eurip. Orest. 1642.)

2. A son of Deucalion, and king of the Ozolian Locrians in Aetolia. His dog is said to have given birth to a piece of wood, which Orestheus concealed in the earth. In the spring a vine grew forth from it, from the sprouts of which he derived the name of his people. (Paus. x. 38. § 1; Hecat. ap. Atlhen. ii. p. 35.)