When developing an original storyline or storyboard for NG, or Ninja Generation, I had to look at our world and the current context in which the word 'ninja' is used. Normally it was arbitrated to mythical warriors during the Sengoku period in which the popular anime, and manga Naruto also draws it's inspiration from. Taking a leaf from Kishimoto-sensei in this, it is easy to see how the shinobi from old faded into obscurity but what if they hadn't? What if the world was totally different from the world we know today, and instead of fading they were hidden from public until they were needed.
It is common knowledge that the modern day ninja can be considered the special ops programs of every country on earth, so why would it be so hard to consider a shinobi in modern times? This is where we draw inspiration for the story of Ninja Generation and where you will decide the fate of the world. Will the world continue in it's peace or will it sink itself into a state of never ending chaos? That is the legend you will write as part of the Ninja Generation.
The planet we inhabit and the world we create is different from our current course of history. While it is still within the Goldilocks section of the solar system. The year is shorter, however since time is relevant to gravity it wouldn't matter so much. The world is much younger because of this however, doesn't make it anymore modern I guess, but it's something to note. It seemed the world developed inventions much sooner than we had in our own, the wheel, religion, bronze and iron weaponry, government, gunpowder, electricity, radio transmissions, etc.
In this world countries developed the same way as countries of our world, however