The harmonica was developed in Europe in the early part of the 19th century. Free-reed instruments like the sheng were fairly common throughout East Asia for centuries and were relatively well known in Europe for some time.
While Christian Friedrich Ludwig Buschmann is often cited as the inventor of the harmonica in 1821, other inventors developed similar instruments at the same time. Mouth-blown free reed instruments appeared in the United States, South America and in Europe at roughly the same time. The reason it was made was so it could be used for classical music.
However, in 1964 — 57 years ago today — Billboard Magazine reported that the harmonica was making a comeback in a big way. The article credited Bob Dylan, the Beatles, the Rolling Stones and Steve Wonder for the renaissance.
Today, the harmonica is known for its use in the blues, American folk music, jazz, country and rock and roll.