Karl Marx was a man who lived a life of contradiction: An angry agitator who spent years in scholarly silence in the British Library Reading Room. A family man who got the housekeeper pregnant. A brilliant mind who argued against exploitation, but lived off wealth exploited from workers in Engel's family mills. Yet despite the paradoxes, this philosopher's ideas had a greater influence in a shorter time than any other thinker in history. During his lifetime he was a little-known, impoverished intellectual, living on the charity of friends and spending his days reading and writing. But within seventy years of his death in 1883, almost a third of the entire human race was living under governments that called themselves by his name - Marxist. Host Bettany Hughes begins her journey in the city of Trier on the banks of the Mosel in Germany. It was here on May 5, 1818 that one of the most important philosophers of the 20th century was born.