It all goes back to 17th-century English writer John Dryen.
Dryden twice stated an opposition to preposition stranding. In an afterword for one of his own plays, he criticized Ben Jonson for doing this, saying: “The preposition in the end of the sentence; a common fault with him, and which I have but lately observed in my own writing.” Later, in a letter to a young writer who had asked for advice, he wrote: “In the correctness of the English I remember I hinted somewhat of concludding [sic] your sentences with prepositions or conjunctions sometimes, which is not elegant, as in your first sentence.”
Dryden does not state why he finds this to be “not elegant.” And yet somehow this completely unexplained, tiny criticism, buried in his mountain of works, lodged itself in the grammarian mind, and continued to be taught for hundreds of years later. This casual little comment would arguably be Dryden’s most enduring creation. It’s a little bit sad.
Read the entire piece here.