It is quite rare for etymologists to pinpoint the very first use of a word or phrase. In this case, however, the eighteenth-century actor and playwright Colley Cibber, in his Lives of the Poets, recounted the exact events that spawned the idea of ‘stealing thunder’. Alexander Pope also mentioned them in his poem The Dunciad. The story they tell involves a man called John Dennis, an actor-manager of the early part of the eighteenth century who had invented a machine that reproduced for the stage the sound of thunder.
Dennis used his invention for the first time in his own play, Appius and Virginia, performed at Drury Lane Theatre in London in 1709. By all accounts Mr Dennis’s writing skills did not match his creative ones, and his play closed after a short run, to be replaced by a production of Macbeth performed by another company. Dennis himself went along to the opening night and was outraged to hear his thunder machine being used. The story goes that he stood up and shouted, ‘Damn them! They will not let my play run, but they steal my thunder.’
The phrase seems to have taken a while to enter the language figuratively. The Oxford English Dictionary’s first example of its use is as late as 1900. It is likely, though, that it was used in conversation and particularly within theatrical circles long before then.