I think nearly everyone reading this will be able to relate to the experience of stumbling onto a new band and being completely wowed by the fact that modern bands can sound fresh while also writing songs of such incredibly high quality.
Starting with the late 60’s and early 70’s, the Japanese were absorbing the hard rock and folk rock happening in the West and releasing their unique takes on it. This continued through the rest of the 70’s until Japan become a common Asian fixture among big world tours towards the end of the decade. Scorpions, Judas Priest, and Van Halen played there to sold out crowds, and you can only bet there was an entire scene full of metal bands inspired by these that developed soon after.