Anhalt-Bernburg – Flag in Lexicon and Shop https://www.flaggenlexikon.de/fdtan-b_me.htm
Flag here at price from 35.70 € – The Duchy of Anhalt-Bernburg existed between 1806 and 1863. Its flag or banner was horizontally striped in green and white.
It is believed that the red goes back to the red eagle of Brandenburg, the green