Highly regarded French painter (1830–1903), one of the leading figures of the impressionist movement, best known for his distinctive pointillist style. Significant ALS in French, signed “C. Pissarro,” one page trimmed in size to 3.5 x 6, January 18, 1898. Pissarro writes from the Hotel du Louvre, Paris, to Monsieur Berttner[?], saying that he cannot go to the [offices of] l’Aurore on that day, and asking that B— add Pissarro’s name to the protest against the “terrible trial of the Conseil de Guerre….” The trial in question was one of the most inflammatory incidents in the notorious Dreyfus Affair, which began in 1894, with the treason conviction of Alfred Dreyfus, a Jewish captain in the French army, on evidence that turned out to be inconclusive at best. On January 11, a week before Pissarro wrote the present letter, Count Ferdinand Walsin Esterhazy was acquitted of committing the crime for which Dreyfus had been wrongfully convicted, though the evidence against Esterhazy was overwhelming. Pissarro, like many other prominent figures of the day, publicly expressed outrage at the verdict. On January 13, the newspaper l’Aurore published Emile Zola’s famous open letter, “J’Accuse!,” laying bare the entire disgraceful affair. Zola was convicted of libel and fled to England, though he returned to France in time to witness the fall of the government and Dreyfus’s release following an overturned second conviction. Trimming as noted, small creases to lower left corner tip, and small puncture in lower blank area, otherwise fine, bright condition. A letter of uncommon historic interest! Auction LOA John Reznikoff/PSA/DNA and R&R COA.