In classical antiquity, writers such as Herodotus,Plato,Xenophon,Athenaeus and many others explored aspects of homosexuality in ancient Greece. The most widespread and socially significant form of same-sex sexual relations in ancient Greece was between adult men and pubescent or adolescent boys, known as pederasty (marriages in Ancient Greece between men and women were also age structured, with men in their thirties commonly taking wives in their early teens). Though sexual relationships between adult men did exist, at least one member of each of these relationships flouted social conventions by assuming a passive sexual role. It is unclear how such relations between women were regarded in the general society, but examples do exist as far back as the time of Sappho.
The ancient Greeks did not conceive of sexual orientation as a social identifier as modern Western societies have done. Greek society did not distinguish sexual desire or behavior by the gender of the participants, but rather by the role that each participant played in the sex act, that of active penetrator or passive penetrated. This active/passive polarization corresponded with dominant and submissive social roles: the active (penetrative) role was associated with masculinity, higher social status, and adulthood, while the passive role was associated with femininity, lower social status, and youth.
The most common form of same-sex relationships between males in Greece was "paiderastia" (pederastry) meaning "boy love". It was a relationship between an older male and an adolescent youth. A boy was considered a "boy" until he was able to grow a full beard. In Athens the older man was called erastes, he was to educate, protect, love, and provide a role model for his eromenos, whose reward for him lay in his beauty, youth, and promise.
The roots of Greek pederasty lie in the tribal past of Greece, before the rise of the city-state as a unit of political organization. These tribal communities were organized according to age groups. When it came time for a boy to embrace the age group of the adult and to "become a man," he would leave the tribe in the company of an older man for a period of time that constituted a rite of passage. This older man would educate the youth in the ways of Greek life and the responsibilities of adulthood.