None actually. Tsui Hark and Koan Hui say on a special edition extra DVD (which I recommend) that their intention was a fictitious world. It could have happened 1000 years ago as well as 500 years ago or even in the future as a post apocalyptic environment or even the present. There are some places on this world where people have no electricity at all. Anyway, the conclusion of all that is that Tsui Hark usually always gives hints of the socio-economical situation of the characters and their political as well as geographical environment. In Dao aka the Blade, there is no reference at all. He also shows us a mix of culture in this metaphorical world: Hence the amulet which is clearly christ on the cross. But they call it an amulet. I hope it was of help for you, Radalan.