Ma'ruf the Cobbler : A Tale from the 1001 Nights by Mohamedou Ould Slahi

A poor cobbler flees an abusive marriage and lands, by way of a jinni, in a distant city where an old friend hands him a plan: pretend to be a merchant of impossible wealth, whose legendary caravan simply hasn't arrived yet. The lie works better than anyone expects. He gives away money he doesn't have, marries into royalty, and keeps the story going for as long as he possibly can.

Then the lie collapses, and he has to run — until a stroke of luck while working an honest field turns everything he's been pretending into something real.

A tale from The Thousand and One Nights, retold plainly — for readers seven to ninety, about a lie so big it eventually had no choice but to come true.