Of much greater importance, as illustrating Ivan's literary talent, is his "Correspondence with Prince Kurbsky" (1563-1579), a warrior of birth as good as Ivan's own, a former favorite of his, who, in 1563, probably in consequence of the profound change in Ivan's conduct, which had taken place, and weighed so heavily upon the remainder of his reign, fled to Ivan's enemy, the King of Poland. The abuses of confidence and power, with the final treachery of Priest Sylvester (Ivan's adviser in ecclesiastical affairs), and of Adasheff (his adviser in temporal matters), had changed the Tzar from a mild, almost benevolent, sovereign, into a raging despot. On arriving in Poland, Prince Kurbsky promptly wrote to Ivan announcing his defection, and plainly stating the reasons therefor. When Ivan received this epistle--the first in the celebrated and valuable historical correspondence which ensued--he thrust his iron-shod staff through the foot of the bearer, at the bottom of the Red (or Beautiful) Staircase in the Kremlin, and leaning heavily upon it, had the letter read to him, the messenger making no sign of his suffering the while. Kurbsky asserted the rights of the individual, as against the sovereign power, and accused Ivan of misusing his power. Ivan, on his side, asserted his omnipotent rights, ascribed to his own credit all the noteworthy events of his reign, accused Kurbsky of treason, and demonstrated to the Prince (with abundant Scriptural quotations), that he had not only ruined his own soul, but also the souls of his ancestors--a truly Oriental point of view. "If thou art upright and pious," he writes, "why wert not thou willing to suffer at the hands of me, thy refractory sovereign lord, and receive from me the crown of life?... Thou hast destroyed thy soul for the sake of thy body ... and hast waxed wroth not against a man, but against God." Kurbsky's letters reveal in him a far more cultivated man, with more sense of decency and self control, and even elegance of diction, than the Tzar. He even reproaches the latter, in one letter, for his ignorance of the proper way to write, and for his lack of culture, and tells him he ought to be ashamed of himself, comparing the Tzar's literary style with "the ravings of women," and accusing him of writing "barbarously." In addition to these letters, Kurbsky wrote a remarkable history of Ivan the Terrible's reign, entitled, "A History of the Grand Principality of Moscow, Concerning the Deeds Which We Have Heard from Trustworthy Men, and Have also Beheld with Our Own Eyes." It is brought down to the year 1578. This history is important as the first work in Russian literature in which a completely successful attempt was made to write a fluent historical narrative (instead of setting forth facts in the style of the Chronicles), and link facts to preceding facts in logical sequence, deducing effects from causes.