Societies are defined at their margins. In the ancient Greek world bastards were often marginalized, their affinities being with the female, the alien, the servile, the poor, and the sick. The study of bastardy in ancient Greece is therefore of an importance that goes far beyond the subject's intrinsic interest, and it provides insights into the structure of Greek society as a whole. This is the first full-length book on the subject, and it reviews major evidence from Athens, Sparta, Gortyn, and Hellenistic Egypt, as well as collating and analysing fragmentary evidence from other Greek states. Dr Ogden shows how attitudes towards legitimacy differed across the various city states, and analyses their developments across time. He also advances new interpretations of more familiar problems of Athenian bastardy, such as Pericles' citizenship law. The book should interest historians of a wide range of social topics - from law and the economy, to sexuality and the study of women in antiquity.