Bismarck: A Life by Jonathan Steinberg

Emperor Wilhelm I was once heard to remark that "It is not easy being Kaiser under Bismarck." The remarkable symbiosis of these two men is at the heart of what shaped central Europe through the 19th century, and prepared the way for the ill-fated 20th. Wilhelm, King of Prussia and first Emperor of the new German Reich of 1871, was serene, gentle, wise, a sovereign who loved his nation more than his power, offering his abdication to move for the greater good. Otto von Bismarck, his first minister, convinced him to defy the revolution in the air and on the streets so that together they could build the Germany both aspired to: steering a traditionalist course, increasing Prussian might, with the King at the helm and "his humble servant" (humility never did enter the heady cocktail that was the Iron Chancellor's character) as his enforcer.

Jonathan Steinberg's astute biography brings the reader closer to both. It expertly depicts those turbulent post-Napoleonic decades, and makes a convincing case for the continuing importance of Bismarck. Napoleon changed the character of European politics and life like no other ruler – until Bismarck. Napoleon was an emperor and general; Bismarck was neither. It remains one of the great ironies that this "genius-statesman" never truly held power. His party was a minority in the fledgling governments which, through his own determination, did not weaken the power of the monarchy – the crux of Prussian identity, the army, remained a royal, not a state, force.

He was distrusted, with justification, by the leading parties: the National Liberals, the Catholic Centre Party, the German Conservatives. He alienated even his natural allies, the very friends, mentors and fellow-influential Junkers (members of the Prussian nobility) who had helped him to power. They valued his fire and grit, regarded him as the upholder of the status quo, then realised they had unleashed a force that was no one's creature. By sheer force of personality, Steinberg argues, this complex, brilliant tactician held sway.

For this practitioner of Realpolitik, politics and power were a shifting chessboard. He stayed several moves ahead of his opponents, playing them off against one another, the Austrians against the French against the Russians, pleased to wage war – on the three of them – to cement the Prussian power-base. He pitted the "people", with talk of democracy, against the princes, and wedged himself between king and queen, using tantrums and illness to get his way.

Steinberg is good on the ambivalences of a man who attracted the highest praise and greatest loathing: a national hero, and "the devil incarnate". A convert to the evangelical Lutheranism popular among the Prussian nobility, he was also the introducer of secular schools and civil divorce. A persecutor of Catholics, he triggered the Kulturkampf, the "culture war", while acknowledging the brilliant Catholic parliamentarian, Ludwig Windthorst.

He attended the opening of Germany's largest synagogue in Berlin, while doing nothing to stamp out the anti-Semitism blazing its path through German society. Yet it was a Jew, the socialist Ferdinand Lassalle, who would command his respect until his death. Ironically, "his consorting with Jesuits and Jews" provided young Wilhelm II with his excuse for Bismarck's dismissal in 1890. A fighter for social reform (when it suited his purposes), and universal suffrage, Bismarck ruthlessly stamped out any real dissent.

Affectionate and a brilliant letter-writer, and the most severe of fathers, he thwarted his son's one real love affair. The most powerful man in Germany, he was intolerably lonely and averse to the trappings of power - denying the nation the pomp of a grand funeral, choosing instead a quiet send-off and a simple epitaph: "Here lies a humble servant of the Kaiser." His legacy was, of course, immense and troubled.

Cameos of other figures – General Moltke and minister of war Albrecht von Roon; diarists Christoph Tiedemann and Hildegard Spitzemberg; the King of Bavaria; the Jewish liberal Eduard Lasker, fighting tirelessly for real change; the best friend, American John Motley, the odd rare soul who did stand up to Bismarck – and a nose for quirky detail add to the pleasure of the narrative. This may transpire to be the definitive study of its subject in English, and what a subject! One could end with Queen Victoria's summation of Bismarck: "Wicked". Or Lord John Russell's: "The demonic is stronger in him, than in any man I know." Or Disraeli's more tempered: "He talks as Montaigne writes."

Instead, here is the blood and iron "despot" in less familiar guise, on a May morning in the countryside near St Petersburg, a young diplomat with his career, loves, and life ahead of him: "I lie in the grass, read poetry... and wait for the cherries to ripen."