This is a portrait of World War I through the letters and diaries of its participants, recently uncovered during extensive research across 28 countries for the 10-part Channel 4 series, The First World War, showing during autumn 2003. Combatants, eyewitnesses and victims talk directly to us from within the war itself and from all sides of the conflict. Their testimony - from that of one of Franz Ferdinand's assassins, to the final entry from a French soldier as he revisits the battlefield in 1919 - recounts the complex history of a war whose repercussions changed the world irrevocably.