Eminent German poet (1797–1856), one of the leading literary figures of the Romantic era, whose verses were set to music by such composers as Schubert, Mendelssohn, Schumann, Brahms, Wolf, Strauss, and Wagner. Scarce ALS in French, signed “Henri Heine,” 5.25 x 8.25, Sunday [no date]. Heine writes to the Comtesse Merlin. In full (translated): “An unforeseen and quite sad impediment prevents me from dining with you today. I am sorry and couldn’t be more displeased, for it would have been a great pleasure for me. Please continue to keep me in your indulgent good graces and deign to receive my respectful hommage….” The adjacent leaf bears the address panel. Mild wrinkling and a faint block of uniform toning, otherwise fine condition. Auction LOA John Reznikoff/PSA/DNA and RRAuction COA.