China history has long had a tradition of homosexuality or, as it is known here, male companionship 男宠 (literally: male pet).

The first records of male companionship was during the Spring Autumn period. In both the works of Mozi Exaltation of the Worthy 尚贤 and Xunzi Against Physiognomy 非相, there are clear mentions of relations with men whose looks were comparable to beautiful women.

A term used to describe homosexuality is 'to have Longyang's craving' 龙阳之癖. This comes from an anecdote during the Warring States period. The Wei king Ji Yu 姬圉 and his companion Longyang Jun 龙阳君 were out on a fishing trip, when the latter suddenly broke down sobbing after catching a haul. The Wei king was concerned and asked after Longyang Jun, who explained that he was sobbing for the fish. He said that he was at first delighted with his first catch, but soon forgot about it in the excitement of the later, bigger fish he caught. He then reasoned that even though he now held the king's favour, surely he would soon pale in comparison when later beauties come along. The Wei king was touched and then declared that any who mentioned beauties before himself would be put to death, thus proving his love for Longyang Jun. [from the Strategies of the Warring States, scroll 25, chapter 4 of Wei]

This trend continued into the Han dynasty, where almost every king had his favourite (or even a few favourites) male companion. It started with Liu Bang 刘邦 himself with his bedmate Ji Ru 籍孺, and his sons and decedents also took to having male lovers in addition to female concubines.

The most famous of these would be Dong Xian 董贤, the companion to Han emperor Liu Xin 刘欣. It was said that Liu Xin loved Dong Xian so much, that they often slept together. Once when Liu Xin had to leave for morning court, his sleeve was trapped under the sleeping Dong Xian's head. Unwilling to disturb his lover from his rest, Liu Xin chose instead to cut off that portion of his sleeve, thus giving rise to the term 'passion of the cut sleeve' 断袖之癖. [from the Book of Han, chapter 63]

With time, homosexuality was no longer just a personal choice, but rather like a fashion trend, became a demonstration of wealth and power. During the Jin dynasty, it was not uncommon for men to dress up finely and make themselves as 'pretty' looking as women, and being able to have male companions became a status symbol. Indeed a quarrel between the uncle of Sima Yan 司马炎 (Wang Kai 王桤) and a high-ranking official Shi Chong 石崇 even used the male companions within the family as stakes, betting hundreds against each other in their petty fight.

In the Book of Song it was recorded that such was the popularity of homosexuality that the female attraction was much in decline, resulting in failed marriages. As exaggeration, to an extent, but nonetheless indication that fair from being prejudiced against, homosexuality was quite mainstream in those times.

For a period of time, this trend waned, but then grew to prominence again during the Song and Ming dynasties. Especially in the latter, when special places 象姑馆 (Xianggu houses) were set up as competition to the brothels, pitting male against female prostitutes.

This upturn has two main influences - politically, the Ming emperor Xuande had passed a ban on brothels in 1429, thus accidentally turning men to seeking companionship from the same sex instead. At the same time, the rise of the philosophical ideology campaigned by Wang Yangming 王阳明 sought to dispel the original thinking of reason over lust, instead campaigning that lust and other emotions were part of human nature and thus should not be suppressed.

This change in cultural norms can be seen in its literary works. Famous Ming author Feng Menglong 冯梦龙 included homosexual romances in his love story collection Love History 情史, while even one of the four great classics Dream of the Red Chamber 红楼梦 includes homosexual relations.

Perhaps one of the most famous self-proclaimed Chinese homosexuals was Zheng Xie 郑燮 (also known as Zheng Banqiao 郑板桥), a Qing dynasty scholar and official, and artist. Although most famous for his calligraphy and paintings, his poems have often made his sexual inclinations clear.

Another interesting fact was that the Qing dynasty name for the male prostitute was xiang gong 相公, a term that was also once used to refer to a husband.

Therefore, although homosexuals were not especially noted for being as such in Chinese history, that was probably because it was so much a norm in those times that no one really raised an eye at such behaviour, and only homosexuals who had other notable achievements then had their names recorded.

*edited to add some more sources/titles

It is important to consider how we understand history. In short, we can only draw knowledge and conclusions of the past from sources. Sources are the "records" we use to interpret and argue history. I think to answer your question we have to start at what the available sources are throughout history to get a working knowledge of how homosexuals were viewed at their current time and place in history.

Sexuality is a complex issue in history, how we in 2015 view sexuality and gender identity is unique to our time and place just as it was in all points throughout the past. For instance someone in the future could look at your question on Reddit for research on how homosexuality was talked about in 2015 and get terms like "the community" and "LGBT+" these are terms that have made their way into the mainstream of how we talk as a society only as of very recently. Therefore someone looking on from the future could infer that as a society we are fairly open to talking about sexuality because of the language used on an internet forum and if they research something like "homosexuality in 2015" they will have a ton of useful source information. Unfortunately in the present that source information on homosexuality is not as readily available for many reasons. Think of who controlled information over much of western history (the church, the wealthy, the literate, heads of governance) this is why we know so much based on the interests of those groups.

However over the past few decades more and more research has been done to help unearth new sources and look deeper into current sources to help better understand all of human sexuality.

one book that is worth checking out that can snowball into many other works on LGBT and human sexuality in general especially in American history is [Coming Out Under Fire] (http://www.amazon.com/Coming-Under-Fire-Allan-Berube/dp/0743210719) by Allan Berube.

Another good source is Epistemology of the Closet by Eve Kosofsky Sedgwick. This one should really get you going on queer studies and sexual history.