Maria Margarethe Danzi née Marchand was a German composer and soprano.
Margarethe Marchand was born in Germany. Some sources give her birthplace as Munich and others Mannheim, and it was possible that the family was on tour in Frankfurt on the date of her birth. She was the daughter of the singer, actress and dancer Magdalena Brochard Marchand and Theobald Hilary Marchand, director of the National Theatre of Mannheim. Margarethe studied music and composition in Munich with Franziska Lebrun and in Salzburg with Leopold Mozart. She apprenticed in supporting roles and debuted in 1787 at the age of 12 at the Mannheim Court Theater, performing the title role in 'The Youth' by Johann Jakob Engel.
In 1790 she married conductor and composer Franz Danzi, and performed with him as prima donna of the troupe Domenico Guardasonis on European concert tours. After 1796 Margaret also performed as prima donna at the Munich Court Theatre. She died in Munich of a lung disease.