KALLSTADT, Germany — Herbert Trump did not want to talk about it. Neither did Ilse Trump. Ursula Trump, who runs the Trump bakery in the next village, eventually relented, palms upturned, and sighed: “You can’t choose your relatives, can you?”

The relative in question is Donald J. Trump, president of the United States, multimillionaire, the most powerful man on the planet and a seventh cousin of Ursula Trump’s husband — though in Kallstadt, a sleepy village nestled in the rolling hills of Germany’s southwestern wine country, he is simply “Donald.”

That is not least to avoid confusion with the other Trumps (or “Droomps,” as the name is pronounced in Palatinate dialect) listed in a phone book for the area: Beate Trump, a podiatrist in another nearby village, for example, or Justin Trump, a teenager whose friends say he sometimes gets teased for his coif of orange-blond hair.