ONOMACRITUS was a seer, priest, and poet of Attica about 530-480 n.c. His importance lies in his connexion with the religious movements in Attica during the 6th century. He had great influence on the development of the Orphic religion and mysteries ; and the works of Musmus, the legendary founder of Orphism in Attica, are said to have been reduced to order by him (see ORPHEUS). He was in high favour at the court of the Pisistratidm till he was detected by Lasus of Hermione making an interpolation in an oracle of Musaeus, and was banished by Hipparchus. When the Pisistratidm were themselves expelled and were living in Persia, Onomacritus is said to have furnished them with oracles encouraging Xerxes to invade Greece and restore the tyrants in Athens. He is also said to have interpolated Homer, and has in modern times been considered by some critics to have remodelled the Homeric poems.