The Tolkien Quote Database
"Thank you for your letter ... I regret that I am not clear as to what you intend by arisch. I am not of Aryan extraction: that is Indo-Iranian; as far as I am aware none of my ancestors spoke Hindustani, Persian, Gypsy, or any related dialects. But if I am to understand that you are enquiring whether I am of Jewish origin, I can only reply that I regret that I appear to have no ancestors of that gifted people."
A draft for a response to Tolkien's German publishers inquiry about his ancestry.
Humphrey Carpenter and Christopher Tolkien (eds.), No. 30, The Letters of J.R.R. Tolkien