Karl August II of Saxe-Weimar-Eisenach (born Karl August Wilhelm Ernst Friedrich Georg Johann Albrecht von Wettin) is the 5th and current Grand Duke of the Grand Duchy of Saxe-Weimar-Eisenach (officially Grand Duchy of Saxony since 1903, but rarely used), succeeding his father Wilhelm Ernst in 1923. Currently, he is the youngest reigning prince within the German Empire, being only 23 years old.