It was written by the Canadian historian Margaret MacMillan with a foreword by the American diplomat Richard Holbrooke.

Peacemakers describes the six months of negotiations that took place in Paris, France, following World War I.

The book focuses on the "Big Three", who are photographed together on its cover (left to right): Prime Minister David Lloyd George of the United Kingdom, Prime Minister Georges Clemenceau of France, and President Woodrow Wilson of the United States.

The author argues that the conditions imposed on Germany in the Treaty of Versailles did not lead to the rise of Adolf Hitler and asks whether the Great War was "an unmitigated catastrophe in a sea of mud", or instead was "about something".

During the later part of the war, the British prime minister was David Lloyd George, the author's great-grandfather.