Really? I expected the relationship to go in the other direction. That raises so many questions.
Yup - Japanese Spider-Man is basically the original Power Ranger, hilariously enough.
Was Japanese Spider Man really that popular?
Apparently, yes. Even Stan Lee himself liked the series!
How long did he last?
The series lasted between 1978-1979, and even had its own movie.
Why in blazes did he have a giant robot in the first place?
Apparently, giant robot shows were all the rage in the 70's. It probably also helped with selling toys.