Douglas Smith, the author of a substantial, meticulously researched and fluently written new life of Rasputin, calls it “possibly the most recognised name in Russian history”.

Everyone knows the story: Rasputin the mad monk; Rasputin the insatiable satyr; Rasputin the faith healer who bewitched a hysterical empress; Rasputin, whose crazed advice destroyed an empire; Rasputin the indestructible, who survived poison, bullets and the freezing river his assassins threw him into; Rasputin, whose very name in Russian means something akin to “libertine”.

The reality as set out by Smith is, of course, less sensational and rather more interesting. Rasputin, a peasant from Siberia, was married with children. In 1892 he decided to devote himself to the life of a religious traveller, like some figure out of Dostoyevsky. He began to acquire the aura of a holy man, and impressed those who met him with his piety and spiritual gifts. At Kazan on the Volga he made the contacts that led him to St Petersburg.

Rasputin: ‘He died like any other man.’ Photograph: Popperfoto/Getty Images

There he was seduced. He became a lion in the salons, which had so often run after fashionable mystics in the past. In November 1905 – with Russia gripped by revolution – he met the imperial family. Within days, according to a letter unearthed by Smith, he was addressing the tsar on matters of national policy. He soon became an intimate associate. The empress was convinced of his ability to calm, if not cure, her haemophiliac son. Rumours seeped into the public: that Rasputin was increasingly interfering in matters of state; that he was systematically seducing some of the highest women in society.

The rumours became much more vicious with the outbreak of the first world war. The tsar was said to be taking his advice on military matters. Empress Alexandra – originally a German princess – was said to be consorting with the enemy. Obscene stories and cartoons began to circulate about her and Rasputin. People in high places muttered that he should be done away with.

Rasputin was an extraordinary but minor figure. He contributed little to the tragedy that was to engulf Russia

Smith has picked apart the sensational myths of Rasputin’s murder. Some facts are clear. Rasputin went to the palace of Prince Felix Yusupov for a late supper on 16 December 1916. Present were Yusupov, the tsar’s nephew Grand Duke Dmitri Pavlovich, and a senior monarchist politician, Vladimir Purishkevich. One or more of them shot Rasputin. The third bullet, to the head, was fatal and he was dead when they threw him in the nearby river. The autopsy showed that Rasputin had taken no poison and there was no water in his lungs. He had died like any other man.

The imperial family were distraught. Alexandra arranged for the body to be buried near her summer palace, but it was dug up and destroyed when the 1917 revolution began. The murderers were questioned by the police, but suffered no serious discomfort.

A fascinating subplot is the role of British ambassador George Buchanan, who did what little he could to avert disaster. Buchanan spoke to the tsar with a freedom few ambassadors would risk today. “I begged his majesty to forgive my frankness… [He] was at the parting of the ways. One road led to victory and a glorious peace – the other to revolution and disaster.” But he knew the tsar was dully incapable of changing course. Russians love conspiracy theories and many are convinced British secret agents were behind Rasputin’s murder. It is wholly unlikely. Smith has searched the files and found nothing convincing.

Rasputin was an extraordinary but minor figure. He contributed little to the tragedy that engulfed Russia in the first two decades of the 20th century. Far more important were a grossly incompetent monarch in the shape of Nicholas II, a ruthless revolutionary in the form of Lenin, and a world war that the Russian government was no more able to avert than any other. All combined to bring down a nation that, if left to itself, might perhaps have become what so many Russians have hoped for, a “normal” and prosperous country.

Rasputin is published by Macmillan (£25). Click here to order a copy for £20.50