Question: Who is John I, Prince Of Anhalt-Bernburg's paternal grandfather?
Sentence (from "Bernhard IV, Prince of Anhalt-Bernburg"): He was the eldest son of Bernhard III, Prince of Anhalt- Bernburg, by his first wife Agnes, daughter of Rudolf I, Duke of Saxe- Wittenberg and Elector of Saxony.
Relevant evidence: No