Haydn wrote the trumpet concerto in 1796, the year after returning from London, for Anton Weidinger of the Vienna court orchestra, who had built a keyed trumpet able to play a full chromatic scale in every register. The instrument was still unfinished when the score was written; Weidinger waited until 1800 to give the first performance in Vienna. Haydn used the new capability at once — the quiet melody low in the register of the opening movement would have been impossible on a natural trumpet. The keyed trumpet itself was superseded within a few decades by valves.