To start your journey into Ubernorden you may start here with "The Smiling Demon," a tale of high seas adveture and piratical terror.
Later you may want to look at "The Killing Field," a story about Ubernorden past and survival of friends.
Or you can just delve into the newest story, "The Sword of War," a story of war and the necessary sacrifices for victory.
Welcome and enjoy the world in which they lived, fought, and conquered.
Edit: forgot to mention that there is dome data in the databook for your comsumption.