Garry Nelson's Left Foot
Well-known member
Some countries require a degree before you're allowed to teach, and I think Japan might be one of them (someone will correct me if I'm wrong!), but in most of the world a CELTA will stand you in good stead.
You need a degree to get a teaching visa in Japan. If you already have a visa- working holiday, spouse etc then you can find employment teaching without the need of a degree.
Also, the degree need bare no relevance to teaching or English. Just so long as you have a proper university level degree you'll be able to get the work visa.