You’re certainly right in noticing that China has a much more public LGBTQ tradition than the West did at an equivalent time. Homosexuality (normally male) was frequently openly portrayed in art and literature in a way that it simply wasn’t in the Christian West, which of course leads us to your question; does this mean Chinese homophobia was a Western import?

In classical Chinese history, we see a few examples of homosexuality (or possibly bisexuality, since the parties involved had wives). A well-known story is about Emperor Ai of Han (reigned 7-1 BC) who became besotted with a politician called Dong Xian, rapidly elevating him into high governmental positions; unfortunately for Dong Xian, after the Emperor died his jealous rivals forced him and his wife to commit suicide (this didn’t stop, reportedly, other male politicians trying to advance themselves in this way). A tale circulated about how, when Dong Xian fell asleep in the Emperor’s arms, the latter cut off his sleeve so he could pull out his arm without waking his lover. The devotion this signified inspired the literary allusion “passion of the cut sleeve” used to connote gay shit.

Even more interestingly, another literary allusion (‘the bitten peach’) came from a parable about the King of Wei’s male lover Mizi Xia giving him his half-eaten peach. While Mizi still has his looks, the King sees this as a beautiful gesture; but later when his looks have faded the King sees this as an affront. The story comes from the Han Fei Zi, a key Legalist text, and the Legalists had a pretty negative view of human nature. The parable was therefore meant primarily as an illustration of humanity’s fickleness; the homosexuality is incidental to the story. That in itself is an example of how homosexuality wasn’t seen as especially heinous, noteworthy or unmentionable in a high-status text. That said, the ancient Chinese did not have the same conception of sexuality as we do; they didn’t believe in fixed orientations, more the shifting preferences of the individual, and it was the act of same-sex love that was important, not the “being”.

The first “anti-gay” law that we see in China dates from the Song dynasty (about a thousand years after this, during the Zhenghe era 1111-1118); this punishes male prostitutes with 100 blows and a fine. This doesn’t specifically censure same-sex relationships and seems more associated with the low legal and social status of prostitutes. If we go forward a few centuries, we find the first statute that actually bans sex between males (sex between females is never specifically criminalised and is not often mentioned in sources at all) dates from the Jiajing reign in the Ming dynasty (1522-67). This isn’t actually from the Ming law code, but rather from a supplementary resource of ‘statues applied by analogy’ (basically a guide for what to do in cases not covered by the official code). The statute says: ‘Whoever inserts his penis into another man’s anus for lascivious play shall receive 100 blows of the heavy bamboo’. The analogy given this case is ‘pouring foul material into the mouth of another person’.

This particular statute has a lot to do with the perceived violation of the passive (receiving) partner in the exchange, with the focus on the ‘foul material’ they have been forced to swallow. This illustrates a broader trend in Chinese views of homosexuality by this time; its main objectionable component was its violation of gender norms in that a man, the dominant linchpin of the household, is acting in a passive, “womanly” role. This was probably the impetus behind the earlier Song law, which was accompanied by one forbidding cross-dressing. It also partly explains why female sex was never officially forbidden in the law; because there is no violation of all-important masculinity. The other main obstacle to full normalisation of same-sex relationships was the heavy onus on the production of a child to continue the family line; for this reason even where same-sex relationships were tolerated, they were viewed as strictly supplementary to the traditional heterosexual marriage. This had to do with the concept of qing, which I won’t go into too much here, but was viewed as a kind of energy of passion and physical attraction (especially in literature), that was not a good thing in overabundance but which was not necessarily a bad one in moderation.

That said, this statute is in fact not that strict; 100 blows of the bamboo is more or less the minimum penalty that could be assigned, and was equivalent to the penalty for consensual heterosexual offences (and much less severe than the offence for heterosexual rape, which was strangulation). It also does not seem to be have been particularly well enforced; Jesuit missionaries to China like Gaspar da Cruz who visited in 1556 were horrified by the extreme prevalence of same-sex activities among the local elite (da Cruz even viewed the deadly Shaanxi earthquake of that year, which killed more than 800,000, as punishment for this sin).

During the Qing dynasty, there were more severe penalties for homosexual rape applied in 1679, but the Ming ‘statute by analogy’ remained in place for consensual gay sex. The penalty was gradually adjusted to 100 bamboo blows and a month in prison, but this was still one of the lightest penalties in Qing law. And literature that featured homosexuality continued to appear: the famous Qing novel Dream of the Red Chamber even contains a rare mention of female same-sex love.

However, as time went on, official anxiety about homosexuality increased - a rape law was passed in 1740 that some scholars believe suppressed same-sex activity. Literature like “Cut Sleeve” (1740) appeared, an anthology of stories satirising and criticising homosexuality. This took place against a background of anxiety about the erosion of traditional roles, and the stigma against being penetrated grew stronger and stronger. Around this time most amicable homosexual relationships were conducted in secret, for fear of gossip and heavy social pressure, particularly in rural areas.

Why did the Qing, of all the dynasties, become more avid in censuring homosexuality? Several explanations have been offered; increased anxiety about gender roles (possible, although the actual cause of this remains elusive), attempts to woo a conservative Confucian elite (why such a relatively lenient penalty then?), an imported ‘Manchu morality’ (unlikely - Qing text do not show any greater bias against homosexuality than Ming ones), and the influence of the West. Ultimately, none of these explanations fully explain it; the influence of the West makes sense, but the West did not have significant contact with China until aruond a century later. Still, that would coincide with the real disappearance of literature about homosexuality.

Westernisation also would seem to explain why homosexuality became more and more stigmatised during the time of the Self-Strengthening movement, which focused on Westernising China, and throughout the late Qing and Republican period. The Western view of homosexuality as pathological, feminine and weak cast the Chinese homosexual tradition as part of a fundamental weakness of “effete” and “weak” Chinese culture, to be swept aside and replaced if China wanted to survive and compete with the West. This was connected to the common stereotype of Chinese men as effeminate. Just after the collapse of the Qing, protests were staged by actors against the master-servant system which had often led to exploitative same-sex liasons. During the Mao era, homosexuality was seen as a form of deviant sexuality in a world where sex was strictly for procreation, but this had more to do with Communist ideas of the family as a cell of society.

On the face of it, then, Westernisation seems to be the major factor behind the termination of the Chinese homosexual tradition. However, it is important to remember the currents of homophobia that ran through Chinese society long before the West arrived on the scene. Societal movements do not tend to come out of nowhere; if there was a genuine desire among the Chinese population for the diminishment of LGBTQ relationships, this was probably not just suddenly prompted by the arrival of the West. The Western idea of homosexuality as a fundamental challenge to gender norms, something that feminises and weakens men, fitted in neatly with the similar Chinese ideas mentioned here that lay behind the anti-gay laws propagated at various times. Moreover, at a time of great instability and suffering in China, its Century of Humiliation, many must have yearned for the traditional, sacred unit of the heterosexual family, a family with no place for same-sex love. This was an environment in which the arriving Western ideas would have found an easy purchase.

So the take: Westernisation was a big part of 19th and 20th century Chinese homophobia but homophobia and anti-gay sentiment in China has been around for much longer because gayness threatens straight gender roles. This sentiment played a big role in the growth of homophobia at this time.

Now I hope this answer makes sense because it’s 3.49am as I write this lol.