In a comment on the parent article Petrael said: “From months of research in the Japanese culture I have never found that the Imperial line of Japan claims descent from Dragons. They claim descent from Amaterasu, the Sun Goddess.” The situation is not nearly as simple as it may sound. It’s convoluted in the extreme, but I shall do my best insofar as my knowledge. First and foremost, a minor pet peeve of mine; “dragons” and ‘long'(Chinese) or ‘ryu’ (Japan), are not a huge conglomerative lump, regardless of popular regard. Though they sometimes are used to represent some similar Elemental forces (and even this comparison differs widely upon closer examination), they are not the same creature unless you want to say that they are both mythological beings–and one would not attempt I would hope to confuse a Wyvern with a Satyr, or tell one that they are the same thing, if you catch my meaning. ‘Western’ dragons are by and large potrayed as at least appearing to be almost wholly reptilian, very much in the way that most people have become familiar with them through common fantasy fiction. ‘long/ryu’ have much more varied appearances and qualities–they can be avian, picine, mammalian, and indeterminate variants between the three. The “Eastern” part of the world that actually claims. most commonly, descent from “long” is actually several of the regional rulers (or Emperors) of ancient China (From which the ‘Long’ of the Seas are mythologically derived, amongst other things.) As I understand it, Vietnamese mythology also makes a large claim to descent from dragons, but I am much less familiar with that mythos than that of China or Japan. The descent of the Japanese imperial family from ‘long’-like beings is convoluted but there is some evidence to support it, at least in an artistic and syncretic sense. The prototypical creator and creatrix of the Ni Hon Go (Rising Sun Land) are Izanami (F) and Izanagi (M). As many of the more ‘modern’ Japanese beliefs and images are heavily influenced by or derived from Chinese mythology (Shinto basically being a huge multileveled syncretization between Old Religious Taoism and the Aboriginal Ancestor-Worship practices of the original inhabitants of the Island chain, the Ainu–told you it got complicated), many of the older images of Izanami and Izanagi syncretize them with the ancient Chinese images of the progenitors of the universe- Pan Ku (M) and Nu Wa (F)–both of whom were originally portrayed as “Naga”-like beings–that is, serpentine and/or draconian from the waist down. The concept and imagery of the “Naga” comes from the Hindu-Vedic traditions, which has spawned much of the Taoist pantheon and imagery. (Kuan Yin is in fact a female ‘aspect’ or derivation of the Hindu diety Avalokitesvara –in Japan, she’s Kannon, and it pretty much continues in that vein on many fronts.) In the Vedic traditon, there is little to no distinction made between “Naga” and “Dragon/Long”, and the words are frequently used interchangeably. In fact, many scholars have postulated that the “Dragon Kings Of The Sea” of China are actually descended from the Vedic mythology of the Naga Kings, and there’s a large amount of evidence to support that. (That chunk of mythos, as well as much of that which now supports the belief structure of Feng Shui, appears to have first started appearing in Japan around the Jomon period, but it may well have been earlier, it’s hard to say.) What does this all have to do with Amaterasu and Co.? Well, if one postulates that Izanami and Izanagi are derivations of Pan Ku and Nu Wa (which seems likely as much of Japanese mythology is derived similarly) then Izanami and Izanagi would indeed be considered to be of ‘draconian’ descent, and hence so would their children, among them Amaterasu (From which the Imperial line claims their descent) and Susano (who interestingly enough has many ‘draconian’ and ‘serpentine’ associations himself.) The fact that other associations began to be made with Amaterasu later on (most commonly the Phoenix presently due to the fire association, and interestingly enough also derivative of Chinese mythology in which ‘dragon’ and ‘phoenix’ represent both opposing and sychronous forces–‘yin’ and ‘yang’ if you will, or ‘in’ and ‘yo’ in Japanese) would be a fairly recent (at least in terms of mythology and legends) development, and not wholly representative of the original symbology. Additionally, though the Japanese people as a whole may not claim ‘descent’ from dragons, many of the original ‘uji’ (clans) of Japan (notably pre “Kojiki” and “Nihongi”, both of which are frequently-mangled aggregations of older myths and legends that were highly politicised by the Yamato clan to support their rule) considered many different ‘supernatural beings’ to be their ancestors, before Shinto as it is commonly percieved today, and multiple individual ‘uji’ ritual beliefs and practices were aggregated into what it is now. If you look back far enough this information can be found.
 Effectively, when the sanskrit title (Avalokitesvara) is rendered into Chinese, it becomes “Kuan Shih Yin”–“The One Who Hears The Cries Of The World” ( Source: “Kuan Yin: Myths and Prophecies Of The Chinese Goddess Of Compassion”, Martin Palmer and Jay Ramsay with Man Ho Kwok)