Duchy of Saxe-Altenburg
When Johann Wilhelm's son and successor Friedrich Wilhelm I died in 1602, the Duchy of Saxe-Weimar passed to his younger brother Johann II. In 1603 Frederick William's eldest son Johann Philipp received the newly created Duchy of Saxe-Altenburg as compensation. It was an Imperial State in its own right, with a vote in the "Reichstag", for much of the 17th century until the extinction of its ruling line in 1672 when it was inherited by Ernest I the Pious, the Duke of Saxe-Gotha, who had married the heiress.