A German author, musical composer, singer, and Romantic-era artistic patron, she most famously wrote the 1835 work, Goethes Briefwechsel mit einem Kinde (Goethe's correspondence with a child). Her other literary works include An die aufgelöste Preußische Nationalversammlung (1849) and Ilius Pamphilius und die Ambrosia (1848).
She was born Elisabeth Catharina Ludovica Magdalena Brentano. A member of an Italian merchant family living in Frankfurt am Main, she studied at a Fritzlar convent school.
She had an unrequited love for the famous writer, Johann Wolfgang von Goethe; their friendship was cut short when she began engaging in jealous behavior toward Goethe's wife.
She married Romantic poet Achim von Arnim. They raised seven children, including a daughter, Gisela von Arnim, who also became a writer.
She was a close friend of renowned composer Ludwig Van Beethoven.