Anhalt – Flag in Lexicon and Shop https://www.flaggenlexikon.de/fdtanhlt_me.htm
Flag here at price from 35.70 € – Anhalt is a former country of the German Empire, founded in 1863, dissolved in 1945. Its flag or banner showed the colors red, green and white, horizontally striped.
believed that the red goes back to the red eagle of Brandenburg