The black exercise book, estimated to sell for up to £1,200, is a child's view of the momentous period of history shortly before the Russian imperial family was overthrown and murdered.
Maria Grigorievna Rasputina began the diary in 1914 at the age of 15 and confided in its ruled pages the story of her rags-to-riches transition from the rural village of Pokrovskoe in Siberia to the capital, St Petersburg, after her father became a favourite of the tsar.
Rasputin had begun life as a Siberian peasant working the land, but his healing powers endeared him to the tsar, Nicholas II, and his wife, Alexandra, after they discovered that he could alone could heal the bleeding of their haemophiliac son and heir, Alexis.
But because Alexis's illness was kept secret, Rasputin's role was misunderstood. Rumours sprang up that he was a German agent, a member of an orgiastic sect, the lover of the empress and her friend Anna Vyrubova, and the man who influenced political decisions. He became known as the "mad monk".
His presence at court was hated by the aristocrats, but he was a favourite of Alexandra and Anna, whom Rasputin had helped to walk again after a train crash in 1915. Such was the gossip about him that after the February Revolution in 1917, Anna was questioned repeatedly about their relationship before being found to be a virgin in a medical examination.
The propaganda against Rasputin worked. But Maria's diary is written in the innocent language of a teenager unaware that in two years' time her father and the imperial family would be murdered.
"My biography: I was born in 1899 in the village of Pokrovskoe in the county of Tobolsk," she wrote.
"My parents are peasants, simple people. Our family consists of: father, mother, grandfather (my father's father), my brother, sister and myself.
"We all live happily together but sometimes I get cross with my brother and sister, but with my sister I get cross all the time. My father plays an important role because the Sovereign knows him and loves him."
Later entries describe how she played with the imperial children, Alexis and his four sisters, her feelings about the superior school she was sent to and her crush on her tutor.
Rasputin was murdered in 1916, an act which was "the first explosion which heralded the coming collapse," according to John Stuart, Sotheby's Russian expert.
In June 1918, Nicholas, Alexandra and their five children were murdered and Russia was plunged into anarchy.
Maria escaped to the West where she earned her living dancing in cabarets before moving to the United States, where she performed as a lion tamer in a circus.
She wrote a book defending her father and was last heard of living in California.