Karl Pauker was an NKVD

NKVD

The People's Commissariat for Internal Affairs was the public and secret police organization of the Soviet Union that directly executed the rule of power of the Soviets, including political repression, during the era of Joseph Stalin....

 officer and head of Joseph Stalin

Joseph Stalin

Joseph Vissarionovich Stalin was the Premier of the Soviet Union from 6 May 1941 to 5 March 1953. He was among the Bolshevik revolutionaries who brought about the October Revolution and had held the position of first General Secretary of the Communist Party of the Soviet Union's Central Committee...

's personal security until his arrest and execution.

Pauker came from a Jewish family in Lviv, which was then part of Austria-Hungary

Austria-Hungary

Austria-Hungary , more formally known as the Kingdoms and Lands Represented in the Imperial Council and the Lands of the Holy Hungarian Crown of Saint Stephen, was a constitutional monarchic union between the crowns of the Austrian Empire and the Kingdom of Hungary in...

. Prior to the war he was a hairdresser working in the Budapest Opera (Sebag-Montefiore). Pauker served in the Austro-Hungarian army in World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 and was taken as a prisoner of war by the Russians in 1916. Pauker elected to stay in Russia after the revolution and joined the Communist Party in 1918.

Pauker joined the Cheka

Cheka

Cheka was the first of a succession of Soviet state security organizations. It was created by a decree issued on December 20, 1917, by Vladimir Lenin and subsequently led by aristocrat-turned-communist Felix Dzerzhinsky...

 and became Stalin's bodyguard in 1924. Pauker took an active part in the purges including the executions of Grigory Zinoviev

Grigory Zinoviev

Grigory Yevseevich Zinoviev , born Ovsei-Gershon Aronovich Radomyslsky Apfelbaum , was a Bolshevik revolutionary and a Soviet Communist politician...

 and Lev Kamenev

Lev Kamenev

Lev Borisovich Kamenev , born Rozenfeld , was a Bolshevik revolutionary and a prominent Soviet politician. He was briefly head of state of the new republic in 1917, and from 1923-24 the acting Premier in the last year of Lenin's life....

He was dismissed in April 1937 according to Sebag-Montefiore, because he "knew too much and lived too well", he was arrested and executed quietly without trial in August 1937. He was not posthumously rehabilitated.

Famous Swedish writer Jan Guillou

Jan Guillou

Jan Oskar Sverre Lucien Henri Guillou is a Swedish author and journalist. Among his books are a series of spy fiction novels about a spy named Carl Hamilton, and a trilogy of historical fiction novels about a Knight Templar, Arn Magnusson...

 has used K. V. Pauker as a pseudonym

Pseudonym

A pseudonym is a name that a person assumes for a particular purpose and that differs from his or her original orthonym...

on the internet when he has, among other things, criticized Jewish influence in the early Soviet Union.