How did Stepanov notation help later ballet companies reconstruct older ballets?

Stepanov notation, developed in 1892 by a dancer at the Mariinsky Ballet, was based on an anatomical analysis of movement that allowed for the recording of complex choreography. Because the Mariinsky adopted this system to document its repertoire, it created a vital archive of classical works that might otherwise have been lost.12

The system proved instrumental for later ballet companies through the work of Nicholas Sergeyev, a former member of the Imperial Ballet who fled Russia in 1918 with scores for 21 ballets recorded in Stepanov notation. Sergeyev used these records to re-create and stage major classical works—including Swan Lake, Giselle, The Sleeping Beauty, and The Nutcracker—for Western European companies, most notably the Sadler’s Wells Ballet (now the Royal Ballet). These scores, which served as essential memory aids, provided the foundation for the authentic reconstruction of these ballets in the 20th century.321