Felix Mendelssohn Bartholdy is considered a pioneer representative of 19th century a cappella choral songs. His works as well as his position and relations enabled him to influence the genre of choral singing. Since his impact on choral music can only be fully understood within the context of his time, this thesis does not only analyze musical aspects but also considers his social environment. In addition to the depiction of the development of choral singing, selected stages of his work are brought into focus, among them being Berlin, Düsseldorf, Frankfurt and Leipzig. Aiming at explaining Mendelssohn Bartholdys affinity for a cappella choral song, the thesis analyzes selected examples of his work, while at the same time considering his concept of choral music and his compositional techniques.