Darius I – 73rd Great Khan of the Illustrius Barbarian Horde, Duque San Lorenzo, Marquis de Feltón, Chief of the Zayante, Baron von Whaleyland, Lord Kennedy
You chose a terrible scenario for a definition. I have no idea what that specific scenario is mentioning, but generally it is for what exactly a bibliography should be used for: citing the sources. Many scenarios are based on real historical events, which requires research. The scenario bibliography is where a user can cite the sources that they referenced when creating their scenario. Here's a slightly better example: http://www.daysofwonder.com/memoir44/en/editor/view/?id=4321. The sources are all in French, though.