Seppuku

Was a lesser known thing about history the origination.

You see the thing with it is like most battle field if you where harmed to greatly and made it back but did not die on the battle field then this was a better option then gang green.

Later ir developed into another thing. Although this may seem odd to people this was not as uncommon in ancient world as people would think. The movie Gladiator did the same thing after the first battle as the General was seeing the people that well where not going to make it. They put a spike to the top of the head and drove it in to make sure they did not feel as much as possible.

The thing that makes the Japanese different is that where given the choice to do this by their own hand so to speak. It was if they struggled to much they would then loose the head.

I believe this is how it developed. I am not positive but this was not unique it was only in the most extreme cases that things where done.