Otto IV receiving Beatrix of Swabia as his future wife, 1212. Beatrice or Beatrix of Swabia, 1198 - 1212. Member of the Hohenstaufen dynasty, Holy Roman Empress and German Queen in 1212 as the first wife of the Welf emperor Otto IV. Otto IV, 1175 - 1218. King of Germany and Holy Roman Emperor. From Ward and Lock's Illustrated History of the World, published c.1882.