Not much

*skims posts* Wow, it seems a lot of people want to know what happened to Bou-san... There's not that much information about it, but here's the gist of it:

In the past, Bou-san could see spirits. However, he ended up having a bit of an accident when doing an exorcism and ended up hitting his head. As a result, his brain's wiring changed and he was no longer able to see spirits.

Time-wise, this would've been before the entire Evil Spirits storyline (ie pre-history) but it doesn't specify when other than being a past event. ^_^

Are you asking about the historical aspects of Hong Kong, England, and China or about what's said about Lin specifically? If it's the historical aspects, I can help a little.

For over a century or so, Hong Kong was a British colony. While the official language remained Chinese, the economic structure, the political structure, and to some degree the culture was decidedly Western in its approach. For various reasons that I no longer remember, Britain returned all control of Hong Kong back to mainland China in 1997. Officially, the Hong Kong citizens were guaranteed to be allowed to maintain their Western approaches to politics and economics. However many citizens doubted that that guarantee would last. In the years before the handing over of control, there was an exodus of (mostly wealthy) Hong Kong citizens to other countries, primarily England, as they fled the country in the face of the oncoming Communist rule.

Interesting! I'm assuming this wasn't the British Mandate, but something different. I'll have to do more research into this, but you gave me a great start.

I wonder if Lin has any brothers or sisters. Hmm... probably not XD

popping in to add a bit to your summary. I'm not Chinese but as I'm Asian, i do recall a bit about British handover .
As I recall, the British had a 100-years contract with the Chinese government. I think, it basically allowed the British to do what they want with HK as long as they returned it to China after 100 years. At that time British was trying to find a base/port in Asia, which is why they agreed (I think, my history may not be so accurate anymore). But in 1997, the 100 years loan ended and they had to return HK back to China.
Of course, some said this means China gets all the benefit. HK is developed without incurring a cost to them, and they get it all back with addded value.

? Regarding hitting his head? No, the only details are as I mentioned in the first reply regarding the incident. About the only other detail I can recall offhand about his time at Kouya-san is that there were only a few monks there that were really able to get rid of spirits of all the monks there. GH was originally set such that Naru was born in the 70's IIRC. However, things have since shifted forward in time with the manga version. There's no absolute date setting.

Yay! Fic! ^^;