I’m not sure whether anyone is interested in any more long posts about Japanese Buddhism. This doesn’t even have too much relevance to anime. Anime often has references to Buddhism in general but it rarely singles out specific sects. (Exceptions: X (TV) has a lot of references to Shingon, and Air (TV) makes oblique references to the history of the Tendai and Pure Land sects.)
Nevertheless I ended up with a lot of notes on this subject and I think it’s worthwhile to post them somewhere. Some of this stuff is actually pretty cool, even if you don’t find it referenced in anime.
The first Buddhist missionaries arrived in Japan from the mainland in the middle of the 6th century CE, and by the early 7th century six sects had built temples in and around the capital. These were the Ritsu, Joujitsu, Kusha, Sanron, Hossou and Kegon sects. None of them made much effort to convert the common people. They were primarily sponsored by wealthy courtiers who hoped that by financing the construction of temples and monasteries they would gain spiritual benefits and worldly success. These sects are not particularly important in Japan today.
In 794 Emperor Kammu moved the capital from Nara to Kyoto, then called “Heian-kyo,” thus beginning the Heian period of Japanese history (794-1185). The move undercut the sects that built their temples around Nara, and opened the way for the rise of some new, more broadly-based sects.