According to
The Oxford Companion to Music, William Corbett was a notable violinist and composer of instrumental music. He spent much time in Italy, ostensibly engaged in musical activities (he was a great collector of Italian violins and music), but it was said he was really a spy on the movements of the Old and Young Pretenders.
Dr. Paul Rubardt goes on to say in a foreword to
Sechs Sonaten (Peters No. 4507) that he was musical director at the opening of the London opera house in the Haymarket in 1705 and at the same time musical director at the Lincoln's Inn Fields Theatre. Later he was a member of the Queen's Band and finally until 1747 of the Royal band of Music. He died in London, bequeathing his valuable collection of instruments, which he acquired during many visits to Italy (after 1711), together with a maintenance fund, to Gresham College.
William Corbett also has a Sarabande published in
Aus Alt-England: Old English Airs and Dances