[...] If I can bring together Germany's best singers, male and female, for the purpose, I propose to perform my operas here in Paris next spring from about the end of April to the middle of June, with a model German company, closing a repertoire of alternating performances with a first production of Tristan. I shall not lack a good French impresario and guarantor, but before I can take up the matter more seriously I must be sure that the singers I choose will come at my call and make this important and most difficult enterprise financially possible by moderating their demands, for honour's sake and for mine. As frequent performances will be necessary to cover the enormous expenses, I must provide for the double casting of the most exacting rôles. Accordingly, everything depends in the first instance on whether the best exponents of my work will have enough sympathy with my extraordinary fate, exiled now, and probably for ever, from Germany, to moderate their claims and make the enterprise practicable.
I count in the first place [...] on you, and ask you to cheer me soon with a favourable reply.
As regards my immediate projects, I have arrived at a crisis which I can only tell you of verbally. Only I assure you of this much, that your visit may prove decisively efficacious for me. [...]
Source: Letters of Richard Wagner, Vol. 2, selected and ed. Wilhelm Altmann, trans. M. M. Bozman (J. M. Dent & Sons, 1927), No. 448