How did the role of religion differ between feudal japan and feudal europe

That's an interesting question. Feudal Japan had a more formalized and ritualized kind of culture than feudal Europe did; elaborate rules of courtesy applied at all levels of society, whereas European peasants were pretty crude for the most part. In both societies there was a unifying religious principle, which in Europe was Christianity and the authority of the Church, and in Japan was shintoism and the authority of the Emperor. In both cases, a social hierarchy attempted, with considerable success, to control everyone's lives; everyone owed their fealty to someone, except for the kings in Europe or the Emperor in Japan, who didn't owe loyalty to anyone, since there was no higher authority (at least, not counting deities). Both societies had similar types of weaponry (European armor was considerably tougher) and skilled swordsmen were much to be feared and respected. In the lower classes, life was cheap. Neither society had any concept of human rights; only the nobility had rights.

The amendment process.