Musical Offering was the lasting outcome of a visit by Bach to the court of Frederick II of Prussia, subsequently known as Frederick the Great. During the visit the king gave Bach a theme and asked him to improvise upon it. Upon his return home, Bach decided to write a series of movements, made up of two ricercars, ten canons, and a four-movement trio sonata, which he published under the title Musicalisches Opfer, sending a dedicatory copy to Frederick. Of special note is that the instrumentation includes a flute, of which Frederick was a keen player.