Conservative historian, poet and Presidential Medal of Freedom winner Robert Conquest passed away on Monday, leaving behind a legacy of vital support for freedom.

Robert Conquest was born in 1917, the son of a British mother and an American father. He is best known for his book “The Great Terror: Stalin’s Purge of the Thirties,” published in 1968.

The work brought to light the true nature of Communism and the Stalin regime, its sheer brutality and inhumanity. Written at a moment when strong pronouncements about the nature of communism were not in vogue in academic circles, Conquest’s detailed exposé of the 20 million people killed between 1937 and 1939 in the Soviet Union eviscerated any claim of Soviet moral superiority.

Robert was educated at Winchester College, the University of Grenoble and Magdalen College, Oxford. A veteran of the Second World War, Conquest briefly served as a British diplomat posted at the United Nations in the 1950s.

His true passion, however,was as a historian and poet. He was a prolific writer, chronicling life under Soviet communism in works including “Russia After Khrushchev,” “Kolyma: The Arctic Death Camps”and “The Harvest of Sorrow: Soviet Collectivization and the Terror-Famine.”

In 1978, Robert Conquest became a distinguished visiting scholar at The Heritage Foundation, serving as one of Heritage’s first distinguished scholars. Over the years, Conquest also worked for the Hoover Institution, Harvard’s Ukrainian Research Institute, the Russia Institute at Columbia University, and Woodrow Wilson International Center for Scholars.

His writings helped guide the thinking and attitudes in regards to the Soviet Union on both sides of the Atlantic.

Conquest’s writings influenced Ronald Reagan as well as Margaret Thatcher, whom he first met when she was leader of the opposition. He and Thatcher shared a moral and political clarity in regards to the Soviet Union, and his writing and advice would be called upon often by the Iron Lady. He helped draft Thatcher’s influential 1975 speech to the Chelsea Conservative Association, where the future prime minister laid out a foreign policy vision of strength and unity in the West while attacking the hypocrisy and moral bankruptcy of the Soviet Union.

In 2006, President George W. Bush presented Robert Conquest with the Medal of Freedom, the highest civilian honor the United States can bestow. Bush’s description of Conquest as a “wise and eloquent man greatly admired by his fellow Americans-and by all who love freedom” echoes true.