Mohammed Beck Hadjetlaché was born Kasi Beck Akhmetukov on May 20, 1868, in Istanbul, Turkey. He grew up in a Circassian family that had fled Circassia after the Russian-Circassian War. When he was young, his father, a leader of a Bashi-bazouk group, was killed during the Russo-Turkish War in 1878. After this tragedy, the family faced many challenges.

In 1882, when he was around 14 years old, Hadjetlaché and his family emigrated to Russia. There, he was adopted by a childless couple, the Ettinger family, who gave him the name Grigory. As he grew older, he became interested in writing. In the 1890s, he began publishing novels and short stories under the pen name Hadjetlaché.

During World War I, in 1916, Hadjetlaché offered his services to the Russian government. He wanted to run a propaganda campaign that would target Germans and Turks, especially in the Muslim communities around the world. By 1917, he was recruited by MI1c while working in a British propaganda unit called the Anglo-Russian Commission in St. Petersburg.

In 1918, Hadjetlaché left Soviet Russia and moved to Sweden. There, he organized a group called the "Russian League." This group aimed to fight against the Bolsheviks. Hadjetlaché settled in a house in the woods outside Stockholm. 

In 1918, Mohammed Beck Hadjetlaché moved to Sweden after leaving Soviet Russia. He organized a group known as the "Russian League" to fight against the Bolsheviks. Hadjetlaché and his gang accused people of being Bolshevik agents and brought them to a house he owned in the woods outside Stockholm. There, they killed the accused and disposed of their bodies by dumping them in a nearby lake.

In 1919, police discovered the bodies of three victims in Norrviken Lake. The victims were Karl Calvé, Juri Levi Levitsky, and Nicolai Ardachev. Hadjetlaché kept a "death list," which suggested that there might have been more victims than those found.

Hadjetlaché's actions became part of a propaganda campaign by the Soviet press, and his story was included in a novel by writer Alexei Tolstoi. On May 28, 1920, Hadjetlaché was sentenced to death by guillotine for the murders. This sentence was later commuted to life in prison due to a moratorium on the death penalty. He died in Långholmen Prison in 1929 after a failed attempt to have his sentence reduced.

Hadjetlaché's accomplices received prison sentences that ranged from six months to eight years. He is noted as the last person to receive a death sentence in Sweden.