It's been theorised that the name was derived from "Drumpf" (alternately Drumpft), which dates back to the 16th century. Information on when the spelling changed varies, Gwenda Blair identified Hanns Drumpf who moved to Kallstadt in 1608. And that the spelling of his last name had changed by the end of the 17th century. Meanwhile, in 2011, the International Business Times repeated an unverified claim that Donald Trump's paternal grandfather Frederich Trump changed his name from Drumpf to Trump, and in 2019, DW Akademie reported from Kallstadt that there were no more people with the surname and that according to the city's transportation association the spelling had likely been changed around the turn of the 19th century.