If your uncle pinched Churchill’s car in 1919, it would have been a Rolls-Royce loaned to him by his friend the Duke of Westminster. It might well have been black. (In my original article for The Automobile I wrote: “His Napier was sold by 1917, when Churchill returned to Whitehall as Minister of Munitions. He went on to the War Office and Air Ministry (1919-21) and the Colonial Office (1921-22). He mainly used government cars—and, through mid-1919, a Rolls-Royce Silver Ghost loaned by his friend “Bendor,” the Duke of Westminster. He considered buying a used Charron landaulette, but experience prevailed and he avoided another French adventure.”)

I know the claims about the SS Jaguar. A claim was also made that Chartwell offered $1m for the car, but Chartwell has no record of this. Several of us went round and round on the story, but in the end were never able to find any documentary evidence that Churchill ever owned one, much less that the King gave one to him, which seems improbable. (King George V died around the time the SS was coming out, and if George VI ever gave him one, it is not documented in the Churchill or other archives.) Randolph Churchill owned a Jaguar, maybe Sarah Churchill did too, but that’s as close as their father ever got to the marque.

I’d be interested in any provenance you found on the SS Jaguar. There is one claimed by its owner to have been Churchill’s, but the only SS Jaguar I could track belonged to his son Randolph. Also, the Rolls-Royce Silver Ghost was owned only briefly, and sold in 1921, before he had acquired Chartwell. Historians suggest it reminded him too much of the loss of his 2 1/2-year-old daughter Marigold, and he couldn’t bear to keep it.

I can find no trace of it.

That’s an interesting connection! Churchill was between cars in 1919, having sold his Napier in 1916. Until 1921, when he bought a Rolls of his own, he borrowed a Silver Ghost from his friend “Bendor,” the Duke of Westminster. That must have been the one your uncle pinched. Clearly he had good taste.

Nothing in the Archives on a Mercedes (or a Benz, which one source states he owned). It turned out to be a garage that specialized in Benzes which did some work on his Mors. Do you have any references?