The administrative structure of Braunschweig was as follows: In 1820 existed 5 districts, Blankenburg, Harz, Schöningen, Weser and Wolfenbüttel. The cities of Braunschweig and Wolfenbüttel had their own administrations. In 1825 Braunschweig sees the separation of courts and genereal administrations. Now six offices are responsible for genereal administrative purposes. Added to the five previous administrations is now the Leine-district. In 1833 six new districts were formed. They are Blankenburg, Braunschweig, Gandersheim, Helmstedt, Holzminden and Wolfenbüttel.
Here is an online gazetteer of Braunschweig