The ancestors of Richard Dawkins, the atheist campaigner against superstition, intolerance and suffering, built their fortune using slaves, it has been revealed.
He has railed against the evils of religion, and lectured the world on the virtues of atheism.
Now Richard Dawkins, the secularist campaigner against "intolerance and suffering", must face an awkward revelation: he is descended from slave owners and his family estate was bought with a fortune partly created by forced labour.
One of his direct ancestors, Henry Dawkins, amassed such wealth that his family owned 1,013 slaves in Jamaica by the time of his death in 1744.
The Dawkins family estate, consisting of 400 acres near Chipping Norton, Oxfordshire, was bought at least in part with wealth amassed through sugar plantation and slave ownership.
Over Norton Park, inherited by Richard Dawkins's father, remains in the family, with the campaigner as a shareholder and director of the associated business.
One Dawkins family member was a member of the clergy. Many were MPs including two who became prominent opponents of the abolition of slavery, eventually achieved thanks to William Wilberforce, an evangelical Christian.
Professor Dawkins, the atheist evolutionary biologist and author of The Selfish Gene, claimed associating him with his slave-owning ancestors was "a smear tactic".
"One of the most disagreeable verses of the Bible – amid strong competition – says the sins of the father shall be visited on the children until the third or fourth generation," he said.
The family's association with Jamaica began when William Dawkins, a direct ancestor of the former Oxford University professor, arrived on the island. He began relatively humbly, as an overseer, probably supervising slaves, before receiving 1,775 acres of land between 1669 and 1682.
His son Richard became a leading member of Jamaican society, serving as a colonel in the local militia.
One history records that when Richard died in 1701 he left "personal property valued at £6,659 in Jamaica currency, [including] 143 negroes 'young and old' valued at £2,784."
Richard's son Henry Dawkins (1698-1744) – another direct ancestor of the campaigner - married Elizabeth Pennant, thus forming an alliance with another one of Jamaica's most powerful planter families.
An inventory of his estate shortly after his death showed that he, his wife and children owned a total of 1,013 slaves valued at £40,736. By 1754 his three surviving sons owned 25,000 acres in Jamaica between them.
Henry's brother James bought Over Norton in 1726. After his death in 1766, the estate passed to his nephew Henry Dawkins (1728-1814), another direct ancestor, who also owned thousands of acres in Jamaica.
Three of that Henry's sons became MPs. The youngest, also called Henry, (1765-1852), was the campaigner's great-great-great grandfather.
In 1796 the oldest son James Dawkins (1760-1843) voted against Wilberforce's proposal to abolish the slave trade, helping to defeat it by just four votes.
In 1807 he was one of a small rump of die-hards opposing the provisions of Slave Trade Act, which abolished selling slaves in the British Empire.
He is believed to have been among just 18 MPs who supported an amendment to postpone the act's implementation by five years. They were defeated by the votes of 174 MPs.
On religious matters James Dawkins was throughout 1813 an opponent of 'Catholic relief', one of the acts which lifted restrictions on freedom of worship, property and electoral rights for Catholics.
James and Henry's brother George Hay Dawkins Pennant (1764-1840) was another defiant slavery supporter. In 1831, two years before the act abolishing slave ownership in the Empire, he signed a circular which insisted: "the speedy annihilation of slavery would be attended with the devastation of the West India Colonies … with inevitable distress and misery to the black population.'"
The Anti-Slavery Reporter of June 1831 was so outraged that it listed 41 signatories including Dawkins, "By way of securing a lasting record of them. They are names which ought not to be forgotten."
In an unwitting anticipation of a later Dawkins's opposition to religion, the Anti-Slavery Reporter also castigated Jamaica's rulers for making slaves work on Sunday: they couldn't worship and were condemned to "toil and secularity".
Prof Dawkins established the Richard Dawkins Foundation for Reason and Science offering a "clear-thinking oasis" supporting secularism. The foundation's 'mission statement' says it is on a "quest to overcome religious fundamentalism, superstition, intolerance and suffering."
In 2010 Richard Dawkins wrote an obituary for his father, describing how John Dawkins had inherited Over Norton Park from a distant cousin and how the estate, in the Cotswolds area of outstanding natural beauty, had been in the family since the 1720s. He omitted, however, to mention how previous generations made their money.
He quoted Scripture – disparagingly - to insist: "I condemn slavery with the utmost vehemence, but the fact that my remote ancestors may have been involved in it is nothing to do with me.
"One of the most disagreeable verses of the Bible – amid strong competition – says the sins of the father shall be visited on the children until the third or fourth generation."
Audibly irritated, he added: "You need a genetics lecture. Do you realise that probably only about 1 in 512 of my genes come from Henry Dawkins?
"For goodness sake, William Wilberforce may have been a devout Christian, but slavery is sanctioned throughout the Bible."
Richard Dawkins' sister Sarah Kettlewell, 67, is thought still to live on the estate, which has a farm shop and pedigree cattle. According to Companies House records which list Professor Dawkins as a director, Over Norton Park Limited made a £12,000 profit last year.
He insisted: "The estate is now a very small farm, struggling to make its way, and worth peanuts. The family fortune was frittered away in the 19th Century. Such money as I have is scarcely inherited at all."
He is now facing calls to apologise and make reparations for his family's past.
Esther Stanford-Xosei, of Lewisham, south London, the co-vice chairman of the Pan-African Reparations Coalition in Europe, said: "There is no statute of limitations on crimes against humanity.
"The words of the apology need to be backed by action. The most appropriate course would be for the family to fund an educational initiative telling the history of slavery and how it impacts on communities today, in terms of racism and fractured relationships."
The revelations come after a difficult few days for the campaigner.
On Tuesday 14 February, some critics branded him "an embarrassment to atheism" after what many listeners considered a humiliation in a Radio 4 debate with Giles Fraser, formerly Canon Chancellor of St Paul's Cathedral, in which the professor boasted he could recite the full title of Charles Darwin's "The Origin of Species", then when challenged, dithered and said: "Oh God."