Silvius Leopold Weiss was an extraordinary lutenist and composer of lute music. About 650 of his compositions have survived to the present day, making him the most prolific lute composer in history.
Weiss was a contemporary of Johann Sebastian Bach. Although he is much less famous, the skill of Weiss, as a composer and performer, has often been compared favorably with that of Bach. Many people think that Weiss would have become much better known if he had written more than just lute music.
The genius of Weiss is difficult to describe, it is far better to hear his music. A good place to start is with a recently posted radio documentary about Weiss. This page also contains some nice audio examples of his music.