Hugh Gaitskell was a British politician, leader of the Labour Party from 1955. He died after a sudden attack of SLE in 1963, aged 56, and left an opening for Harold Wilson in the party leadership.

The abrupt and unexpected nature of his death led to speculation that foul play was involved, the most popular conspiracy theory involving a KGB plot to ensure that Wilson (supposedly a KGB agent himself) became prime minister. This claim was given new life by Peter Wright’s controversial 1987 book Spycatcher