I ran across a reference to these S&W guns when I was researching my Lanchester smg.
(Background )
The British 9mm Parabellum LANCHESTER Mk1 was a copy of the German MP-2811, and was used by the British Navy during WW2.
Designed by George Herbert Lanchester in 1941, the gun was manufactured by the Sterling Engineering Company, Dagenham, Essex, England.
When Britain went to war in 1939, there were no sub-machineguns of any sort in her Order of Battle. In fact, the armories were bare. It was not until 1940 that the British Purchasing Commission in New York was instructed to buy all the Thompson sub-machineguns that it could lay its hands on. In all, orders were placed for 300,000 Thompson sub-machineguns and a staggering 249 million rounds of .45 cal. ammunition. (100,000 never ended up in Britain but rather at the bottom at the Atlantic Ocean ,…casualties of the German U-Boats etc.)
Once the gold reserves were gone it was a case of necessity that Britain, in desperation, just had to manufacture her own sub-machinegun.
After evaluation and debate the decision to manufacture a gun that resembled the German MP28 (11) was made, …leading to the development of the British Lanchester MK.1 sub-machinegun.
Who got the Lanchesters?
50,000 Lanchesters: (nearly) All for the Royal Navy.) First contract June 13, 1941.
The first order was supposed to be split 50-50 between the Royal Navy and the Royal Air Force, which did not happen.
By this time the British Army had supplies of the Thompson, and they made it quite clear that the Thompson was what they wanted, so the Army kept the Thompson.
The Royal Air Force would immediately receive the 2,000 newly acquired Smith & Wesson 9mm carbines (smgs), for the defense of aerodromes and airfields now springing up around the country.
(Ironically the RAF had originally requested a copy of the German MP38.)
way over complicated.
