Der Blaue Reiter was an influential artist group of the early 20th century and is considered one of the most important pioneers of modern art. Founded in 1911 by Wassily Kandinsky and Franz Marc, the group advocated for free and expressive art, breaking away from realistic depictions and instead focusing on color, form, and spirituality. The outbreak of World War I in 1914 abruptly ended the movement, but its ideas significantly influenced the development of abstract art and Expressionism. Today, Der Blaue Reiter is regarded as one of the key movements of Classical Modernism.