Brian Help!!!

Yeah, So Pat & I have this test tonight in 390 about Japanese History. Basically what we have here are hundreds of years with a different ruler every other year; that is a shitload of rulers eaching ruling in different time periods based on where the capitol is.....I want to die. Basically I have no idea how I am going to write an essay in a blue book about this shit...I hate blue books.... What the hell happened to multiple choice? I'm in the wrong damn department here...So, anyone w/ some fluent knowledge in Japanese History available? Brian? Help me...........