From the Pulitzer Prize-winning author of Khrushchev: The Man and his Era comes the definitive volume on one of the most important and controversial figures of the 20th century. When Mikhail Gorbachev became its leader in March 1985, the USSR was still one of the world's two superpowers. By the end of his tenure six years later, the Communist system was dismantled, the cold war was over and, on 25th December 1991, the Soviet Union itself ceased to exist. While not solely responsible for this remarkable upheaval, he set decisive changes in motion. Assessments of Gorbachev could not be more polarised. In the West, he is regarded as a hero. In Russia, he is widely hated by those who blame him for the collapse of the USSR. Admirers marvel at this vision and courage. Detractors, including many of his Kremlin comrades, have accused him of everything from naivete to treason.