Complex sentence: Through the marriage of Hildegard von Henneberg, areas of the Bergstraße passed to Henry II of Katzenelnbogen in 1135, who was ennobled as an earl in the year 1138 by King Konrad III. At that time Auerbach belonged to the County of Katzenelnbogen.
Split into simpler sentences: Through the marriage of Hildegard von Henneberg, areas of the Bergstraße passed to Henry II of Katzenelnbogen in 1135. Henry was ennobled as an earl in 1138 by King Konrad III. At that time, Auerbach belonged to the County of Katzenelnbogen.