David Rees wrote:

> As an explanation for what propelled the TWL/AW/FQ sequence it has
> more to say to me then any amount of digging round the literary
> sources used to build them. It was still disappointing to find not
> much more about Verdenal as an influence on TWL. Its still not clear
> when TSE was suppposed to have learnt of JV's death. [But suppose on
> his flight from Viv through France with the the components of TWL;
> suppose TSE then tried to look up his former friend, and then found
> out that he had been killed?]

Verdenal was killed 2 May 1915.  The Eliot's were married 26 June
1915.  A letter to Conrad Aiken in January 1916 indicates that Eliot
definitely knew of Verdenal's death by this time ("Letters," p. 125).
Eliot visited Paris in December 1920 and stayed at the smae pension
that he and Verdenal lived in during 1910-1911.  He wrote his mother
about this in January 1911 ("Letters", p. 433). "If I had not met
such a number of new people there Paris would be desolate for me with
pre-war memories of Jean Verdendal and the others."

Probably the most you will find on Verdenal (but still not much) is in: 
    Watson, George. "Quest for a Frenchman," The Sewanee Review 84
    (summer 1976) pp. 466-475. 
For how Verdenal influenced "The Waste Land":
    Miller, James E., Jr. T.S. Eliot's Personal Waste Land:
    Exorcism of the Demons.
    University Park: The Pennsylvania State University Press, 1977 
Also of interest may be:
    Miller, James E., Jr. "T.S. Eliot's 'Uranian Muse':
    The Verdenal Letters," ANQ, Vol. II, No. 4, (fall 1998) pp 4-20 

    Rick Parker