Pyotr Nikolayevich Durnovo (born 1845, Moscow province, Russia—died Sept. 24 [Sept. 11, old style], 1915, Petrograd) was a Russian statesman and security chief under tsars Alexander III and Nicholas II, who brutally suppressed the revolution of 1905. He is also noted for a remarkable memorandum he wrote in 1914 in which he accurately foresaw the course of the coming World War, including the collapse of the Russian Empire.
Durnovo resigned from military service to enter the government. His rise thereafter was rapid, and he became director of the Russian police in 1883. During his tenure in this post he was instrumental in breaking up the terrorist organization that had assassinated Alexander II. Dismissed in 1893 after a sex scandal, Durnovo returned to the government in 1900, this time as assistant minister of the interior, becoming acting minister under the moderate prime minister S.Y. Witte in late October at the height of the Russian Revolution of 1905.
A determined rightist, Durnovo quickly won the confidence of Nicholas II by dint of his effective suppression of the St. Petersburg and Moscow soviets. Durnovo was dismissed along with Witte in 1906 in the aftermath of the disorders, but he was soon appointed to the State Council, and he quickly became the leader of its conservative elements. Serving on the council until his death in 1915, he opposed all efforts to dilute the power of the monarchy.