Margaret MacMillan on the Assassination of Franz Ferdinand and Sophie

July 16, 2014 12:19 PM EDT

The assassination of Archduke Franz Ferdinand and his wife Sophie on June 28, 1914, is widely seen as the central, precipitating event of the First World War: the spark that lit the conflagration. Here, historian and bestselling author Margaret MacMillan, whose masterful The War That Ended Peace is now in paperback, considers a single photograph of Franz Ferdinand and Sophie made just hours before their violent deaths—and discerns in the sunny scene the seeds of chaos and unfathomable destruction.

We see a pleasant couple on a sunny morning. They are a little plump, perhaps, and well into middle age. Clearly they are people of wealth and consequence. They are sitting in an expensive open car, a rarity at the time. She is elegant in a white dress and hat. Although the photograph is black and white, we know from other sources that the flowers she carries are roses, blood-red ones. He is wearing a military uniform. As she looks on approvingly, he shakes the hand of a local dignitary.

The man leaning down from the car is Archduke Franz Ferdinand, heir to the throne of Austria-Hungary, that vast and ancient empire at the heart of Europe. By his side is his wife, Sophie. As it happens, they are about to celebrate their wedding anniversary. By all accounts the marriage has been a very happy one. Nevertheless, the old emperor and his court disapprove of her because she comes from the wrong social class and they humiliate her at every opportunity. But today Franz Ferdinand and Sophie are in Sarajevo, far from Vienna and its rigid etiquette, and she is being received with full honors as his equal.

The photograph was taken a hundred years ago, on June 28 1914, and they have less than three hours to live. Young assassins, backed and armed by shadowy forces in Serbia, are waiting among the onlookers. Even then, the couple so nearly escape their fate. One bomb misses and others among the plotters lose their nerve. Then, while trying to flee, the driver of the car takes a wrong turn. As he fumbles with the gears to back up, the last of the assassins steps up and shoots the passengers, point blank.

Five weeks later, Europe’s great powers were at war. Austria-Hungary, with Germany’s backing, took the opportunity of the assassinations to move against Serbia; that in turn brought in Russia to defend the little Balkan nation; Germany went to war with Russia and its ally France; and Britain came to their defense. The fighting lasted for four years and drew in other powers, from Japan to the United States. It left more than 9 million soldiers dead, destroyed empires, and fueled ideologies such as fascism and communism. We cannot look at the photograph made on that sunny day in Sarajevo without the awful knowledge that the deaths of that smiling man and woman were going to change the world forever.

Margaret MacMillan is the Warden of St Antony’s College and a Professor of International History at the University of Oxford. Her books include Women of the Raj (1988, 2007); Paris 1919: Six Months that Changed the World (2001), for which she was the first woman to win the Samuel Johnson Prize; and her most recent, The War That Ended Peace: The Road to 1914, among others. She is a Fellow of the Royal Society of Literature and a Senior Fellow of Massey College, University of Toronto, Honorary Fellow of Trinity College, University of Toronto and of St Hilda’s College, University of Oxford. She has honorary degrees from the University of King’s College, the Royal Military College, The University of Western Ontario, Ryerson University, Toronto and Huron University College of the University of Western Ontario.

Archduke Franz Ferdinand (seated, in hat) and his wife, Sophie, on the day they were assassinated, Sarajevo, June 28, 1914.The LIFE Picture Collection/Getty Images

A Picture Before Dying: Franz Ferdinand and Sophie, Sarajevo, 1914

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