Darwin made virtually no mention of humans at all in "The Origin of Species" Further, popular political writing 150 years ago and even later commonly used "race" to mean nationality; we read from those times about the "Irish race" and the "English race." In fact, Darwin considered all human biological variation he observed in his worldwide travels merely due to differences in climate and diet. For example Charles Darwin, wrote in The Descent of Man, and Selection in Relation to Sex (John Murray, London, 1871), "It may be doubted whether any character can be named which is distinctive of a race and is constant."
Note that this is at a time when many Christians argued that non-Europeans were not even human! The American slave owners were assured by the "preAdamites" that God had created the Negro with the "beasts of the field" and that the sons of Adam (of course all Whites) was only exercising his God ordained right to dominate these sub-humans. Christian racists in America even to this day maintain that nonwhites are subhuman, cite biblical support for slavery, and/or allege that Blacks are descended from Ham, the son of Noah who was cursed to be a mere servant.
Darwin's attitude toward Africans was shaped in part by his early friendship with a Negro man he became friends with in Edinburgh. Darwin learned the art of taxidermy from him and whom he mentioned in his autobiography; "By the way, a Negro lived in Edinburgh, who had traveled with Waterton and gained his livelihood by stuffing birds, which he did excellently; he gave me lessons for payment, and I used often to sit with him, for he was a very pleasant and intelligent man." -- Charles Darwin, Autobiography of Charles Darwin 1809-1882 (restored edition)(1958), Nora Barlow editor, p.51. Darwin also mentioned this in his 1871 book, “The Descent of Man;”
“The Races of Men”
Although the existing races of man differ in many respects, as in colour, hair, shape of skull, proportions of the body, &c., yet if their whole organisation be taken into consideration they are found to resemble each other closely in a multitude of points. Many of these points are of so unimportant or of so singular a nature, that it is extremely improbable that they should have been independently acquired by aboriginally distinct species or races. The same remark holds good with equal or greater force with respect to the numerous points of mental similarity between the most distinct races of man. The American aborigines, Negroes and Europeans differ as much from each other in mind as any three races that can be named; yet I was incessantly struck, whilst living with the Fuegians on board the “Beagle,” with the many little traits of character, shewing how similar their minds were to ours; and so it was with a full-blooded negro with whom I happened once to be intimate.
“Now when naturalists observe a close agreement in numerous small details of habits, tastes and dispositions between two or more domestic races, or between nearly-allied natural forms, they use this fact as an argument that all are descended from a common progenitor who was thus endowed; and consequently that all should be classed under the same species. The same argument may be applied with much force to the races of man.” (London: John Murray, 2nd Ed. 1874:179)
I want to emphasize that Darwin's anti-slavery, and anti-racism was 40 years before Abraham Lincoln’s Emancipation Proclamation.
Further, Charles Darwin was an ardent abolitionist at a time when many used the Bible to justify slavery. In 1833 he wrote, "I have watched how steadily the general feeling, as shown at elections, has been rising against Slavery. What a proud thing for England, if she is the first European nation which utterly abolishes it. I was told before leaving England, that after living in slave countries: all my options would be altered; the only alteration I am aware of is forming a much higher estimate of the Negro's character." Charles Darwin to Catherine Darwin (May 22 - July 14 1833) The Correspondence of Charles Darwin Vol. 1 1821-1836 (1985), pp. 312-313
Abolitionists William Wilberforce, and Thomas Clarkson were funded by Charles R. Darwin’s Grandfathers; Josiah Wedgwood and Erasmus Darwin, through the Society for Effecting the Abolition of the Slave Trade. Wedgwood and Darwin were founding members in 1787, and served on the London Committee. It was Clarkson who in 1791 conceived the British boycott against slave labor sugar. But it was Wedgwood money that paid for the thousands of pamphlets used to promote the campaign.
The Darwin and Wedgwood opposition to slavery spanned generations. In 1824 the family provided significant financial support to the Anti-Slavery Society run by W. Wilberforce and Thomas Fowell Buxton (Wilberforce’s successor to the House of Commons in 1818). The anti-slavery slogan, “The Universal Father has made of one blood all nations” was coined by a Shrewsbury Unitarian and prefaced anti-slavery resolutions introduced to Parliament.
So young Charles R. Darwin was raised in the center of anti-slavery and anti-racist activism.
I want anyone confused by the creationist propaganda to read;
Daly, John Patrick
2002 "When Slavery Was Called Freedom: Evangelism, Proslavery, and the Causes of the Civil War" Kentucky University Press
Desmond, Adrian and James More
2009 “Darwin’s Sacred Cause” New York: Penguin Books
Consider The Rev. John Bachman (February 4, 1790 – February 24, 1874). He was an American Lutheran minister, social activist and naturalist who collaborated with J.J. Audubon, Co-founder of Newberry College, and Lutheran Theological Southern Seminary. Bachman published in 1850 “The Doctrine of the Unity of the Human Race Examined on the Principles of Science,” and in 1855 “Characteristics of Genera and Species, as Applicable to the Doctrine of Unity in the Human Race.” Bachman was liberal of his place and time. He accepted that the African, and Caucasian races were of the same species. However, he also wrote that the African were of such "an inferior, and debased nature" that it was the Christian Duty of Whites to enslave the Africans “for their own good.”
There is a long tradition of racism in the American Christian churches, especially the Southern Baptists who split from the Northern Baptists and supported slavery. See for example;
1862 “Proof of Slavery From the First Chapter of Genesis” Publisher unknown
1934 "Tracing Our White Ancestors: White Roots" (1962 ed. Phoenix, Az: Lord's Covenant Church) and 2009 reprinted as "Tracing Our Ancestors: Traces the European American Back to Father Abraham and Beyond" Muskogee, Ok: Artisan Publishers.
2008 “The Aryan Jesus: Christian Theologians and the Bible in Nazi Germany” Princeton University Press
Modern creationist Henry Morris's (founder of the Institute for Creation Research) wrote in "The Beginning Of the World, Second Edition (1991), pp. 147-148:
"The descendants of Ham were marked especially for secular service to mankind. Indeed they were to be 'servants of servants,' that is 'servants extraordinary!' Although only Canaan is mentioned specifically (possibly because the branch of Ham's family through Canaan would later come into most direct contact with Israel), the whole family of Ham is in view. The prophecy is worldwide in scope and, since Shem and Japheth are covered, all Ham's descendants must be also. These include all nations which are neither Semitic nor Japhetic. Thus, all of the earth's 'colored' races,--yellow, red, brown, and black--essentially the Afro-Asian group of peoples, including the American Indians--are possibly Hamitic in origin and included within the scope of the Canaanitic prophecy, as well as the Egyptians, Sumerians, Hittites, and Phoenicians of antiquity."
So, Christians and modern creationists support racism, and slavery as "biblical."