Russia lost her foremost man of letters at this period by the death of Count Alexander Sergeyevich Pushkin, as the result of a duel. His last work, the drama "Boris Goudunov," was left uncompleted. After his recall from his exile in Bessarabia, Pushkin had been appointed as imperial historian by Czar Nicholas, in which capacity he wrote a history of Peter the Great and an account of the conspiracy of Pugatshev. Of his poetic works, the most important was "Eugene Onegin," an epic written after the manner of Byron's "Don Juan." "Eugene Onegin" has remained one of the classics of Russian literature throughout the Nineteenth Century. Pushkin's brother poet Lermontov, then an officer of the Guards, wrote a poem demanding vengeance for Pushkin's death. He was banished to the Caucasus, and his writings were suppressed. Under a false name he now wrote his famous epic: "Song of Czar Ivan Vasilyevitch." [Sidenote: The first kindergarten] [Sidenote: German clerical struggle] A joyful event in German letters was the great festival at Mainz in honor of Gutenberg and his invention of the art of printing. Froebel opened his first kindergarten at Blankenburg in Thuringia. Auerbach, the popular novelist, brought out his "Spinoza." Much was made by Germans of the opening of the first railway between Dresden and Leipzig, and of the invention of coal-tar colors, or aniline dyes, by a process destined to revolutionize the arts of coloring and dyeing throughout the world. A great stir was created by the imprisonment of the Archbishop of Cologne at Minden after a quarrel with the Prussian Government concerning marriages between persons of different creeds. He was forbidden to go to Bonn. Backed by the Holy See in Rome, he continued to defy the Protestant authorities. [Sidenote: Death of William IV.] [Sidenote: Victoria's accession]