Originally I didn't have a prologue. I started in the heat of battle. People were confused because I hadn't established the world yet, and were subsiquently emotionally distant from the characters.
It bombed.
This issue will climax with a battle, but I felt the need to establish the human element first and give the reader a reason to care about the action.
Starting with a prologue won't bring the reader any closer to the characters and does nothing for world building. What you have is a bunch of info dumping, which makes the story drag. Don't make the mistake in thinking you don't need to study writing techniques to write a manga/comic book. You use the same techniques in both the written novel and the graphic novel. If you want the reader to care about the MC, then you get into his head, so to speak. Feel what he feels, see what he sees and show it with your pictures, i.e. the horror of the war, the sadness of losing loved ones, the destruction. Walk along side him and experience the world with him.
You bring empathy to the reader by having the MC act as the reader would in the same situation. I.e. I'm watching "Apollo 13" and Tom Hanks looks out of the ship's window to the earth below and at the same time, his wife looks at the sky from her window in her house. There's that connection that brings tears to the audience's eyes b/c they understand the fear of losing a loved one and the connection married people have. It's as if they are talking to each other. In fact, I have the movie on mute now and I still get the same impact without the music and words b/c of the people's body language and facial elements.
In otherwords, you want to show the emotions through your pictures. That makes the reader care about the characters.
As for world building, you weave that into the background, through dialogue, culture traits, sexual roles, family roles, etc. A prologue won't do it for you.
I suggest you go through the Writing with Uncle Jim thread in the novels section and the Sci-fi section under genre. This will help you understand more about writing and world building. Good luck!!
kim