Question

Approximately when and how did Buddhism come to Japan? (Needs some explanation)

Answer 1

" Mahayana Buddhism was introduced to Japan from Korea in the sixth century (traditionally, in either 538 or 552, as part of a diplomatic mission that included gifts such as an image of Shakyamuni Buddha and several volumes of Buddhist text)."- google

hope this helps :)

Answer 2

The historical history of Buddhism actually started when Buddhism was introduced. Aproximatly 1450 decades ago during the Nara period.