Ostracism was political device invented by Cleisthenes whereby an Athenian who was thought to represent a threat to democracy could be voted into exile for a period of ten years. One might say that it was a kinder and gentler form of exile. This slide shows the actual ostraka used in the ostracisms of some well know Athenian politicians, including Themistocles, the Athenian general/statesman, more responsible than anyone else for the creation of an Athenian navy in the early 5th century.