In the early 20th century, Russell led the British "revolt against idealism". He is considered one of the founders of analytic philosophy along with his predecessor Gottlob Frege, colleague G. E. Moore and protégé Ludwig Wittgenstein. He is widely held to be one of the 20th century's premier logicians. With A. N. Whitehead he wrote Principia Mathematica, an attempt to create a logical basis for mathematics. His philosophical essay "On Denoting" has been considered a "paradigm of philosophy". His work has had a considerable influence on mathematics, logic, set theory, linguistics, artificial intelligence, cognitive science, computer science (see type theory and type system) and philosophy, especially the philosophy of language, epistemology and metaphysics.
Russell was a prominent anti-war activist and he championed anti-imperialism. Occasionally, he advocated preventive nuclear war, before the opportunity provided by the atomic monopoly had passed and "welcomed with enthusiasm" world government. He went to prison for his pacifism during World War I. Later, Russell concluded that war against Adolf Hitler's Nazi Germany was a necessary "lesser of two evils" and criticized Stalinist totalitarianism, attacked the involvement of the United States in the Vietnam War and was an outspoken proponent of nuclear disarmament. In 1950, Russell was awarded the Nobel Prize in Literature "in recognition of his varied and significant writings in which he champions humanitarian ideals and freedom of thought".
Bertrand Russell was born on 18 May 1872 at Ravenscroft, Trellech, Monmouthshire, into an influential and liberal family of the British aristocracy. His parents, Viscount and Viscountess Amberley, were radical for their times. Lord Amberley consented to his wife's affair with their children's tutor, the biologist Douglas Spalding. Both were early advocates of birth control at a time when this was considered scandalous. Lord Amberley was an atheist and his atheism was evident when he asked the philosopher John Stuart Mill to act as Russell's secular godfather. Mill died the year after Russell's birth, but his writings had a great effect on Russell's life.
His paternal grandfather, the Earl Russell, had been asked twice by Queen Victoria to form a government, serving her as Prime Minister in the 1840s and 1860s. The Russells had been prominent in England for several centuries before this, coming to power and the peerage with the rise of the Tudor dynasty (see: Duke of Bedford). They established themselves as one of the leading British Whig families, and participated in every great political event from the Dissolution of the Monasteries in 1536–1540 to the Glorious Revolution in 1688–1689 and the Great Reform Act in 1832.