Ancient Greece is known for its acceptance of bisexual behavior.
In classical antiquity, writers such as Herodotus, Plato, Xenophon, Athenaeus and many others explored aspects of same-sex love in ancient Greece. The most widespread and socially significant form of close same-sex sexual relations in ancient Greece was between adult men and adolescent boys, known as pederasty. (It is important to note, however, that marriages in Ancient Greece between men and women were also age structured, with men in their 30s commonly taking wives in their early teens.) 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 Western societies have done for the past century. Greek society did not distinguish sexual desire or behavior by the gender of the participants, but by the extent to which such desire or behavior conformed to social norms. These norms were based on gender, age and social status. There is little extant source material on how females viewed sexual activity. There are two main views of male sexual activity in ancient Greek society. Some scholars, such as Kenneth Dover and David Halperin, claim that it was highly polarized into "active" and "passive" partners, penetrator and penetrated, an active/passive polarization held to be associated 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. In this view, any sexual activities in which a male penetrated a social inferior was regarded as normal; "social inferiors" could include women, male youths, foreigners, prostitutes, or slaves; and being penetrated, especially by a social inferior, was considered potentially shameful.
Other scholars, however, argue that male-male relations usually involved an adult male and a youth: the older male took the active (penetrative) role. They also describe them as "warm," "loving," and "affectionate,"  and argue that the Greek tradition of same-sex relations was central to "Greek history and warfare, politics, art, literature and learning, in short to the Greek miracle."
The most common form of same-sex relationships between males in Greece was "paiderastia" meaning "boy love". It was a relationship between an older male and an adolescent youth. In Athens the older man was called erastes, he was to educate, protect, love, and provide a role model for his beloved. His beloved was called eromenos whose reward for his lover lay in his beauty, youth, and promise.
Elaborate social protocols existed to protect youths from the shame associated with being sexually penetrated. The eromenos was supposed to respect and honor the erastes, but not to desire him sexually. Although being courted by an older man was practically a rite of passage for young men, a youth who was seen to reciprocate the erotic desire of his erastes faced considerable social stigma.
The ancient Greeks, in the context of the pederastic city-states, were the first to describe, study, systematize, and establish pederasty as a social and educational institution. It was an important element in civil life, the military, philosophy and the arts. There is some debate among scholars about whether pederasty was widespread in all social classes, or largely limited to the aristocracy.
The morality of pederasty was closely investigated in ancient Greece, some aspects being considered base and others idealized as the best that life had to offer. In Plato's Laws, carnal pederasty is described as "contrary to nature"; and effecting a law against it -in the words of the Athenian interlocutor "probably such a law would be approved as right"- would be popular among the Greek city-states.
In the military
The Sacred Band of Thebes, a separate military unit reserved only for men and their beloved youths, is usually considered as the prime example of how the ancient Greeks used love between soldiers in a troop to boost their fighting spirit. The Thebans attributed to the Sacred Band the power of Thebes for the generation before its fall to Philip II of Macedon, who was so impressed with their bravery during battle, he erected a monument that still stands today on their gravesite. He also gave a harsh criticism of the Spartan views of the band:
- "Perish miserably they who think that these men did or suffered aught disgraceful."
Pammenes' opinion, according to Plutarch, was that
- "Homer's Nestor was not well skilled in ordering an army when he advised the Greeks to rank tribe and tribe... he should have joined lovers and their beloved. For men of the same tribe little value one another when dangers press; but a band cemented by friendship grounded upon love is never to be broken."
These bonds, reflected in episodes from Greek mythology, such as the heroic relationship between Achilles and Patroclus in the Iliad, were thought to boost morale as well as bravery. They typically took the form of pederasty, with more egalitarian relationships being rarer. Such relationships were documented by many Greek historians and in philosophical discourses, as well as in offhand remarks such as Philip II of Macedon's recorded by Plutarch demonstrates:
- "It is not only the most warlike peoples, the Boeotians, Spartans, and Cretans, who are the most susceptible to this kind of love but also the greatest heroes of old: Meleager, Achilles, Aristomenes, Cimon, and Epaminondas."
During the Lelantine War between the Eretrians and the Chalcidians, before a decisive battle the Chalcidians called for the aid of a warrior named Cleomachus. He answered their request, bringing his lover to watch. Leading the charge against the Eretians he brought the Chalcidians to victory at the cost of his own life. The Chalcidians erected a tomb for him in the marketplace in gratitude.
Love between adult men
Given the importance in Greek society of cultivating the masculinity of the adult male and the perceived feminizing effect of being the passive partner, relations between adult men of comparable social status were considered highly problematic, and usually associated with social stigma. However, examples of such couples are occasionally found in the historical record.
Achilles and Patroclus
The first recorded appearance of a deep emotional bond between adult men in ancient Greek culture was in the Iliad (800 BC). Although Homer does not explicitly depict the relationship between Achilles and Patroclus as sexual, by the beginning of the Classical era (480 BC) the two heroes were interpreted as pederastic icons.Template:Fact Since the ancient Greeks were uncomfortable with any perception of Patroclus and Achilles as adult equals, they tried to establish a clear age difference between the two. There was disagreement on whom to make the erastes and whom the eromenos, since the Homeric tradition made Patroclus out to be older but Achilles dominant. Other ancients held that Achilles and Patroclus were simply close friends.
Aeschylus in the tragedy Myrmidons made Achilles the protector since he had avenged his love’s death even though the gods told him it would cost his own life. However Phaedrus asserts that Homer emphasized the beauty of Achilles which would qualify him, not Patroclus, as “eromenos”.
Historical adult male couples
Among the historical male couples, where both partners were adults, are Euripides, in his seventies, and Agathon, already in his forties. The legendary love between Alexander the Great and his childhood friend, Hephaistion is sometimes regarded as being of the same order.
Sappho, a poet from the island of Lesbos, wrote many love poems addressed to women and girls. The love in these poems is sometimes requited, and sometimes not. Sappho is thought to have written close to 12,000 lines of poetry on her love for other women. Of these, only about 600 lines have survived. As a result of her fame in antiquity, she and her land have become emblematic of love between women, although she herself may in fact have been bisexual.Template:Fact
Pedagogic erotic relationships are also documented for Sparta, together with athletic nudity for women. Plato's Symposium mentions women who "do not care for men, but have female attachments." In general, however, the historical record of love and sexual relations between women is sparse.
Scholarship and controversy
After a long hiatus marked by censorship of homosexual themes, modern historians picked up the thread, starting with Erich Bethe in 1907 and continuing with K. J. Dover and many others. These scholars have shown that same-sex relations were openly practiced, largely with official sanction, in many areas of life from the 7th century BC until the Roman era.
Although this perspective is the scholarly consensus in North America and Northern Europe, some scholars believe that homosexual relationships, especially pederasty, were common only among the aristocracy, and that such relationships were not widely practiced by the common people (demos). One such scholar is Bruce Thornton, who argues that insults directed at passive homosexuals in the comedies of Aristophanes show the common people's dislike for male homosexuality. Other scholars, such as Victoria Wohl, emphasize that in Athens, same-sex desire was part of the "sexual ideology of the democracy," shared by the elite and the demos, as exemplified by the tyrant-slayers, Harmodius and Aristogeiton. Even those who argue that pederasty was limited to the upper classes generally concede that it was "part of the social structure of the polis." Outside academia, both opponents of LGBT rights and Greek nationalists have latched on to the argument that homosexuality was limited to the elite for political purposes.
The subject has caused controversy in modern Greece. In 2002, a conference on Alexander the Great was stormed as a paper about his homosexuality was about to be presented. When the film Alexander, which depicted Alexander as romantically involved with both men and women, was released in 2004, 25 Greek lawyers threatened to sue the film's makers, but relented after attending an advanced screening of the film.
- Homosexuality in the militaries of ancient Greece
- Philosophy of Greek pederasty
- Greek love
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- Lilar, Suzanne, Le couple (1963), Paris, Grasset; Translated as Aspects of Love in Western Society in 1965, with a foreword by Jonathan Griffin, New York, McGraw-Hill, LC 65-19851.
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- Wohl, Victoria. Love Among the Ruins: the Erotics of Democracy in Classical Athens. Princeton University Press, 2002. ISBN 0-691-09522-1