Harry Kessler, author of the libretto to Richard Strauss's Der Rosenkavalier, lived a full life.

His diary of 1913 shows he dined with Queen Mary, supped with George Bernard Shaw, lunched with Nijinsky and visited Octave Mirbeau, the French novelist. ''We won't have war,'' he was assured by many, including Mirbeau.

In the same year, the Prince of Wales visited Kaiser Wilhelm in his office and found the German leader sitting on a military saddle, claiming it was more conducive than a chair to clear thinking. There might just have been a clue of prospective belligerence in the kaiser's choice of seat, but the prince chose to ignore it.

A year later the world plunged into an orgy of destruction. Charles Emmerson, in a consistently brilliant survey, shows that this was neither inevitable nor expected by many, despite the nagging signs that the tectonic plates of world politics were shifting and that a generation was about to disappear into the subsequent abyss.

Emmerson's book is not a study of how the war began, though there are hints and suggestions about the imminence of conflict throughout the 500 pages. It is rather a study of what was lost and how individual cities stood before the disintegration of 1914-18.

His idea is simple. He has written chapters on individual cities, sketching a portrait of the issues that affected the masses and picking up personalities to illuminate his ideas. The conception of 1913 can thus be described as a smart idea. Its consummation is, frankly, astonishing.

This is Emmerson's second book and he exhibits both a hunger for hard work and a facility for picking the precise detail, making the most devastating point in the most elegant of language. A world that was about to embrace death on a hitherto unimaginable scale is brought to life with wit, sharpness and occasional delicacy.

It is intriguing to note that Berlin was regarded as little more than a garrison town in 1913, that London in many ways was much as it is today in terms of financial power, and that Vienna was at the hub of an empire primed to explode. There is nothing stunning in any of these observations but Emmerson recreates the cities as they were with convincing testimony from committed witnesses. This is a book, too, that roams from Europe to America, China, India and Africa. The author knows he is presaging a world conflict and seeks to place every major city in that context.

The most astonishing chapter is that on Vienna, a city Emmerson restores to its pre-war greatness in terms of influence, culture and brooding threat. But as the world stood on the threshold of mayhem, there is a peek behind the scenes to see what was driving or informing the major figures. Almost incidentally, Emmerson thus gives the best pen picture of Woodrow Wilson this correspondent has read and subtly points to contemporary matters in his investigations on Jerusalem and Tehran.

The mood and uncertainty of 1913 is rendered with a foreboding that only comes with the reader's knowledge of what is to befall the world. This is a world at play, at work and, at higher levels, indulging in almost routine intrigue and manoeuvres. Some were predicting war but, then again, some always are.

Detroit was making cars at an unprecedented rate, the British Empire was making money and, in Paris and elsewhere, the fortunates were making whoopee. Yet as satirist Karl Krauss said, the fields of Europe and beyond were about to become ''a proving ground for world destruction''.

Emmerson's outstanding research and lucid writing thus carries not only the intimation of immediate horror but a warning of the ease with which conflict is engaged. Historians can look back at every war and point to moments that made bloody belligerence the favoured option. Emmerson is more ambitious. He looks at how it was, for the masses and the major players, and brings forth a world that did not have to disappear in the fog of war, recreates cities whose inhabitants were not resigned to or overly worried about a global bloodbath and details the actions of royalty and politicians who were pursuing their agendas with war as a possible but unlikely scenario.

Yet the Great War broke out within a year. Incidentally, Harry Kessler and Kaiser Wilhelm, and presumably his saddle, survived it. More than 37 million people did not.

1913: The World Before

The Great War

Charles Emmerson

The Bodley Head, £25