Alonzo “Lonnie” Johnson (February 8, 1899 – June 16, 1970) was an American blues and jazz singer, guitarist, violinist and songwriter. He was a pioneer of jazz guitar and jazz violin and is recognized as the first to play an electrically amplified violin.

Johnson was born in New Orleans, Louisiana, and raised in a family of musicians. He studied violin, piano and guitar as a child and learned to play various other instruments, including the mandolin, but he concentrated on the guitar throughout his professional career. “There was music all around us,” he recalled, “and in my family you’d better play something, even if you just banged on a tin can.”

In 1917, Johnson joined a revue that toured England, returning home in 1919 to find that all of his family, except his brother James, had died in the 1918 influenza epidemic.

He and his brother settled in St. Louis in 1921, where they performed as a duo. Lonnie also worked on riverboats and in the orchestras of Charlie Creath and Fate Marable.

In 1925, Johnson married, and his wife, Mary, soon began a blues career of her own, performing as Mary Johnson and pursuing a recording career from 1929 to 1936. (She is not to be confused with the later souland gospel singer of the same name.)