Baron Klaus Wulfenbach is reluctant ruler of Europa Wulfenbach, who spends much time in Caledon on matters of international importance serving as his own Consul. He keeps a journal entitled Baronial Notations since first encountering Caledon, but his earlier history and that of his lands are archived in the fanciful graphical accounts by Professors Philip and Kaja Foglio of Transylvania Polygnostic University, accessible at Girl Genius.
The Baron has been acclaimed as being the most talented Spark of his generation. He has a very talented adult son, Gilgamesh, who he hopes will be able to guide the people of Europa into a more mutually-cooperative peace than the overgrown kindergarten situation he maintains with a stern and exasperated hand, and a wife about whom he is quite closemouthed (some suspect it is for her continued safety). He would much prefer to be off studying the nature of the Spark (to quote the Professors Foglio, the Spark is "whatever it is that makes Mad Scientists what they are. A poorly understood concept that identifies and incorporates a batch of personality traits shared by those who have it.") instead of ruling, but he sees his duty as maintaining the peace his best friends, Bill and Barry Heterodyne, originally established before their disappearance.
His family lands were in Central Transylvania until they were ravaged during the aftermath of the Other War. He rebuilt his schloss into a massive airship, a slow-moving floating city in itself, reasonably named the Castle Wulfenbach. The Wulfenbachs themselves are of the Transylvanian ethnic group called "Saxons", Germans hired in the 1100s as mercenaries to guard borders and as miners to improve the local economy, who settled and flourished in their new lands.
Baron Wulfenbach's interests in Caledon and points elsewhere are exploring the nature of interdimensional travel; passively studying the many Sparks of Caledon, Steelhead and other lands; promoting interest in Europa to bolster its economy; and generally getting away from the annoying politics of his "day job". He has become an enthusiastic participant in the social lives of the lands which have accepted his consular mission.
In-world, he has an "ætheric sister" named Melanippe Karas. Assisting the Baron with phenomenal competence are Frau Annechen Lowey, his Vice Consul; his Chancellor, Sir Edward, Earl Primbroke; the Jägermeister Mavromichali Szondi; and other staffmembers of exceptional talent.