Mr. Stravinsky is a famous Russian composer and pianist who lived from 1882 to 1971. He is best known for his pioneering work in the modern classical music genre, which includes works such as The Firebird, Petrushka, and The Rite of Spring. He was also a prolific conductor and teacher, and his influence on the development of 20th century music is still felt today. The answer to the crossword puzzle is 'Igor, ' which is the first name of Mr. Stravinsky.