Robert Conquest was born in England to an Anglo-American family. He attended Winchester and studied at the University of Grenoble before entering Oxford University, where he earned bachelor's and master's degrees in politics, philosophy, and economics, as well as a doctorate in history. As a member of the Communist Party group at Oxford, he traveled to the USSR in the summer of 1937. At that time, he did not understand what was going on behind the façade of the propaganda machine. However, as an officer in the British army during World War II, Conquest witnessed the Soviet takeover of Eastern Europe, and this experience left him firmly disillusioned with Communism. In the late 1940s, Conquest worked as an analyst at the Information Research Department (IRD) of the British Foreign Office. In 1956, Conquest left the IRD, becoming a freelance writer and historian. During the 1960s, he edited eight volumes of work produced by the IRD, published in London as the Soviet Studies Series and in the USA as The Contemporary Soviet Union Series.
In 1962–63, Conquest was briefly the literary editor of The London Spectator. He's the author of 21 books on Soviet history, politics, and international affairs, including his early works Common Sense About Russia (1960), The Soviet Deportation of Nationalities (1960), Power and Policy in the USSR (1961), and Courage of Genius: The Pasternak Affair (1961). In 1968, Conquest published what became his best-known work, The Great Terror: Stalin's Purge of the Thirties, the first comprehensive history of this period. In the 1970s and 1980s, Conquest spurred intense debates within the scholarly community with books on the forced labor camps in Kolyma, on the terror-famine in the Ukraine in 1932–1933, and on the murder of Leningrad’s party chief, Sergei Kirov. He also published 8 volumes of poetry and won the 1945 PEN Brazil Prize for his poem "For the Death of a Poet." In 1981, Conquest moved to California to become Senior Research Fellow and Scholar-Curator at Stanford University’s Hoover Institution. He has also been a fellow at Columbia University's Russian Institute, and at the Woodrow Wilson International Center for Scholars, a distinguished visiting scholar at the Heritage Foundation, and a research associate of Harvard University's Ukrainian Research Institute. He was the host of Red Empire (1990), a Granada Television documentary on the Soviet Union.