Ludwig van Beethoven is the first name people think of when asked questions related to classical music. His symphonies, piano sonatas and choral works are still performed today, especially his symphonies. Beethoven's symphonies are well known to everyone, a good example is his “knock-knock” Symphony No. 5. The rhythmic pattern and minor third jump could be hummed and recognized by many. However, few people are familiar with Beethoven's masses, the Mass in C major opus 86 and the Mass in D, commonly known as Missa Solemnis, opus 124. These two masses are significant because they were written at two different times in Beethoven's life. Beethoven. The Mass in C was written in 1807 and was his first mass written in the traditional style (Solomon 205). The Missa Solemnis was written in 1818 and was not completed until 1823 because Beethoven spent more time playing with it until he was satisfied with it (Schauffler 381). Both masses were written around the same time as his famous symphonies, No. 5 and No. 9 respectively. However, these two masses are not only significant because they were written at two different times in Beethoven's life; they were also written in two different periods of musical history. The Mass in C was written near the end of the Classical period, which lasted from 1750 to 1820. The Missa Solemnis was written at the beginning of the Romantic period, which lasted from 1810 to 1914. Beethoven was at the crossroads of two different musical periods. and he made a successful career in both and by analyzing and comparing the two masses one can see the changes through which Beethoven went. This research will be divided into three sections, the Mass in C, the Mass in D, then a comparison of the two. Each beginning of each mass will contain the story...... middle of paper ......43. Book.Forbes, Elliot. Thayer's Life of Beethoven. Flight. 1. Princeton: Princeton University Press, 1967. Book.—. Thayer's Life of Beethoven. Flight. 2. Princeton: Princeton University Press, 1967. Book. Kerman, Joseph and Alan Tyson. The New Grove Beethoven. New York: WW Norton & Company, 1983. Book.Newman, Ernest. The unconscious Beethoven. New York: Alfred A Knof, 1927. Book. Rosen, Charles. Classical style Haydn Mozart, Beethoven. New York: WW Norton & Company, 1997. Book. Schauffler, Robert Haven. Beethoven, the man who liberated music. New York: Tudor Publishing Co., 1929. Book. Scherman, Thomas K. and Louis Biancolli. Beethoven's Companion. New York: Doubleday & Company, Inc., 1972. Book. Schonberg, Harold C. The Lives of the Great Composers. New York: WW Norton & Company, 1997. Book. Solomon, Maynard. Beethoven. New York: Schirmer Books, 1977. Book.