Seth Lesser (1865 – 1931) was an American pianist, organist, ragtime music composer, and jazz musician.

Lesser’s training in music began when he was just five years old. Although his parents were not musically trained themselves, they nevertheless, recognized that young Seth Lesser had musical talent. They bought him his first pump organ when he was 7 years old and sent him to Julius Johnson, an organist for a local Methodist church, for his piano lessons. By the time he turned 13, Lesser had already mastered a couple of pieces by classical composers Mozart and Chopin.

In his teens, Seth Lesser became less enthusiastic about the formalities of classical music and began to have more interest in ragtime music. By this time, he had already learned how to write in musical notation and began making his own compositions. Living in Maryland, he had a lot of exposure to African-American hymns and tunes which greatly influenced his compositions. He produced the Baltimore Blues in 1985, which artistically combined the ragged rhythm of ragtime music that was heavily marked by the tunes of Chopin’s mazurkas. This was followed by a string of compositions which had been popular for a few years.

When the ragtime music fell out of favor, Seth Lesser moved to New York in 1917 and began playing jazz music while occasionally giving New Yorkers a taste of his genius in ragtime.