One would suppose that the notions of literary topos and humility topos were of ancient origin. Certainly "topos" appears in Aristotle's Rhetoric in the original Greek. However its entry into the academic lexicon as an English word relevant to rhetoric and other literary forms would seem, as far as I've been able to tell, to have occurred at some point in the 20th century.
The online OED confirms this; it does contain "topos", defining it as
"A traditional motif or theme (in a literary composition); a rhetorical commonplace, a literary convention or formula." and the earliest citation it gives is 1948, in Leo Spitzer's "Linguistics and literary history" (presumably referring to Curtius's work).
Interestingly, though, its earliest cited uses of "topic" (16th/17th century) are also as a translation of Aristotle's "topos", and with a similar meaning to Curtius's "topos". -Peter.
1. Volume Ti-Tz of the OED does not contain the word "topos," nor does it appear under the entries for "humility" or "literary." (Ordinarily the OED can relied on to record just about every English word that has appeared in print prior to the 20th century.)
2. Adams Sherman Hill, Boylston Professor of Rhetoric and Oratory in Harvard University from 1876 to 1904, wrote "The Foundations of Rhetoric" in 1892 with no mention of the concept of topos as a notion in rhetoric.
The Wikipedia article on Ernst Robert Curtius at
http://en.wikipedia.org/wiki/Ernest_Robert_Curtius
says "He is best known for his 1948 work Europäische Literatur und Lateinisches Mittelalter. It was a major study of the Medieval Latin literature and its effect on subsequent writing in modern European languages. The book was largely responsible for introducing the literary topos concept as a scholarly and critical discussion of literary commonplaces."
So unless someone comes up with an earlier use, it looks like 1948 may be the date, and German the language, of the first appearance of "topos" outside the original Greek of Aristotle.
-- Peter LeFanu Lumsdaine Carnegie Mellon University [For admin and other information see: http://www.mta.ca/~cat-dist/ ]