Complex sentence: George William (Herzberg am Harz, 26 January 1624--28 August 1705, Wienhausen) was Duke of Brunswick-Lüneburg and ruled first over the Principality of Calenberg, a subdivision of the duchy, then over the Lüneburg subdivision.
Split into simpler sentences: George William (Herzberg am Harz, 26 January 1624--28 August 1705, Wienhausen) was Duke of Brunswick-Lüneburg. He ruled first over the Principality of Calenberg, a subdivision of the duchy, then over the Lüneburg subdivision.