Born November 21, 1873 in Yarmouth, England, Kell was the son of a wealthy family, provided with advanced training, speaking polish and English at an early age. Graduated from the Royal Military Academy in Sandhurst in 1892, fluent in several languages. Including French, German and Italian in addition to the Polish and English.
Served in the British military and was sent to Moscow where he quickly learned Russian. Returned to England where he married Constance Scott on April 5, 1900. Immediately thereafter was sent to China where he fought to put down the Boxer Rebellion.
Returned to London and was transferred to the War Offices' German Desk and was placed on the Committee of Imperial Defense in 1907. Was named director of MO5 (Military Operation 5), the newly developed counter-espionage department in 1909. In 1916, the name of the agency was changed to MI5. Worked alongside of and asked advice from many of the top military and security experts in Britain.
Initiated a purge of spies from throughout England. Kell ordered that the purge take place all at once in order to prevent any from escaping due to being tipped off. Many of the top spies in the country were gathered up in the purge. Later Kell would authorize the hunt for Karl Lody, the top German spy in London.
Enjoyed a heralded career during World War I and into the 1930's, being promoted all the way to the rank of Major-General. Was considered one of the top counter-espionage experts in the world, both for his methods of investigation and for his knowledge of the subject.
Had an acrimonious relationship with Winston Churchill, Britain's Prime Minister during World War II. Speculation was that Churchill held a grudge against Kell for not sharing classified information with him in the 1920's, a period where Churchill was not in power.
On October 14, 1939, a German submarine sent a torpedo into the side of the British battleship the Royal Oak. When the ship sank, 834 men died. Later, in 1940, an explosion occurred in the Royal Gunpowder Factory in Waltham Abbey. Both incidents were initially considered to have been the result of espionage and sabotage undetected by Kell's MI5. Although later investigations tended to prove that this was not the case, Churchill jumped at the opportunity to cast a dark shadow on Kell. On May 25, 1940, Churchill fired Vernon Kell, removing him from his position as the head of MI5.
Crushed shocked and devastated by his dismissal, Kell, having dedicated his life to serving his country was heartbroken and retired to a small cottage in Buckinghamshire where he died on March 27, 1942.