Gay literature is a collective term for literature produced by or for the LGBT community which involves characters, plot lines, and/or themes portraying male homosexual behavior. The term is now used most commonly to cover specifically gay male literature, with a separate genre of lesbian literature existing for women. Historically, the term "gay literature" was sometimes used to cover both gay male and lesbian literatures.
In a historical sense, literature as we understand it is a fairly new innovation, and the current concept of homosexuality is even fresher from the cultural oven. It's no great surprise, then, that gay literature — or even gay characters in literature — are so relatively new as to still be shiny.
Because of the persecution or opposition to homosexuality in many world cultures throughout history, LGBT individuals have often turned to literature as a source of validation, understanding, and beautification of same-sex attraction. LGBT literature may also document the psychological stresses and alienation suffered by the gay community as LGBT individuals confront such challenges as prejudice, AIDS, self-loathing, bullying, violence, religious condemnation, denial, suicide, persecution, and other such obstacles.
Themes of love between individuals of the same gender are found in a variety of ancient texts throughout the world. The ancient Greeks, in particular, explored the theme on a variety of different levels in such works as Plato's Symposium.
Many mythologies and religious narratives include stories of romantic affection or sexuality between men or feature divine actions that result in changes in gender. These myths have been interpreted as forms of LGBT expression and modern conceptions of sexuality and gender have been applied to them. Myths have been used by individual cultures, in part, to explain and validate their particular social institutions or to explain the cause of transgenderism or homosexuality.
In classical mythology, male lovers were attributed to ancient Greek gods and heroes such as Zeus, Apollo, Poseidon and Heracles (including Ganymede, Hyacinth, Nerites and Hylas, respectively) as a reflection and validation of the tradition of pederasty.