Keith Gessen in The Guardian:
Grigory Rasputin was a Siberian peasant turned holy man with incredible charisma, bad teeth, questionable hygiene (he claimed that he once went six months without changing his underwear), and a strong animal odour – like a goat's (according to the French ambassador). He used these various attributes to ingratiate himself with the royal family of Russia and become, for about a year toward the end of the Romanov dynasty, the de facto power behind the throne. While doing all this he seduced thousands of women and still managed to get stone drunk several nights a week. It's an inspiring story, though it ends badly, and no wonder that the expatriated French actor Gérard Depardieu has played Rasputin in not one but two biopics in the last two years.
…Rasputin took advantage of the Russian tradition of the wandering peasant holy man, walking from village to village and reputed to have a direct connection with God (even Tolstoy, toward the end of his life, visited one). He also exploited the loneliness and isolation of the last Romanov couple, Nicholas and Alexandra – the tsar a polite, indecisive man and the tsarina a German-born and English-bred granddaughter of Queen Victoria (“The tsarina was as happy ordering chintzes from the latest Maples catalogue as she was cultivating mystics,” writes Welch), who never quite adjusted to Russian life or shed her accent (she communicated with Nicholas in English). And, finally, he made use of the vexed condition of the couple's son, Alexis, the heir to the Russian throne, who had inherited (from Queen Victoria) a terrible disease: haemophilia. Nicholas and Alexandra kept vigilant watch over the boy, employed two sharp-eyed sailors to accompany him everywhere and commandeered an army of doctors to try to make him well. None of them could do anything; as Welch points out, they may easily have done more harm than good, prescribing, for example, the new wonder drug aspirin, which we now know is an anti-coagulant, the exact opposite of what a haemophiliac needs. The disease was torture for both the boy and his mother. During bleeding episodes Alexis would suffer excruciating pain, and his mother, an empress but also, she knew, the carrier of the disease, would sit by him, helpless.