In 1885, Donald Trump's 16-year old grandfather emigrated from Kallstadt in what is now southwest Germany to the United States. The immigration officer listed his name as "Friedr Trumpf" (see line 33). No later than 1910, Friedrich Drumpf was calling himself Fred Trump, which is how he appears on the US census of that year (image online at ancestrylibrary.com, subscription required). He died at the age of 49 in Queens and is now memorialized by a tombstone that reads "Fred Trump."
I confirmed what details I could from the Wikipedia entry as well as its source article, verifying them against the records available through ancestrylibrary.com (subscription required). Note that although the immigration record linked above (Wikimedia Commons; also on familysearch.org) clearly attests to the name Friedrich, I could not confirm any occurrence of the spelling of his last name as Drumpf. Ancestry and findagrave.com both list his name as Friedrich Drumpf, but neither gives a witness to this particular spelling. While it is certainly plausible that an immigration officer might have heard Drumpf and written Trumpf, Trumpf is also a plausible spelling for a German name derived from Latin triumpus (triumph).
In fact, German Wikipedia includes no notable Drumpfs other than Friedrich himself. And it actually claims that the spelling "Drumpf" is falsified. The article instead calls him by his Americanized name, Frederick Trump, but it points to familysearch.org, which lists his baptismal name as Friedrich Trump. This record points back an additional generation to Donald Trump's great-grandfather Johann Ii Trump. I have no way of confirming these spellings or finding their source, which is a compilation of baptismal records.
According to this encomium, the Drumpf family arrived in Kallstadt in 1608 and changed their name to Trump sometime before 1700. Unfortunately, this claim is not supported by verifiable research and is in fact attached to the unlikely name (for a 17th-century German) of John Philip Trump. So while the deep roots of the Drumpf family tree may or may not prove false, it looks like archival research might be necessary for their final proof.
This submission has been removed because it violates our '20-Year Rule'. To discourage off-topic discussions of current events, questions, answers and all other comments must be confined to events that happened 20 years ago or more. For further explanation of this rule, feel free to consult this Rules Roundtable
Edit: This post does not violate our 20-year rule. My apologies to OP for not reading carefully enough.
