"The German Fuhrer...has consistently sought to make the practice of Germany conform to the theory of evolution." Evolution and Ethics 1947, Sir Arthur Keith p.230

A time-worn Christian Creationist quote-mine. See http://www.talkorigins.org/faqs/quotes/mine/part4.html#DarwinRaceQuotes

Eugenics had plenty to do with evolution, and although it is now called "Pseudoscience" it was accepted for decades. Charles Darwin certainly did not think his cousins work was "Pseudoscience".

In Darwin's time, the primitive cultures found in places like Africa, Australia, the Brazilian Amazon area, the American Indians, etc, were considered savage races due to their lack of civilization. For what it's worth, my original degree was in anthropology, and the history of early anthropological studies of primitive cultures is fascinating, but this didn't happen to well after Darwin's time.

Unlike many of his predecessors and contemporaries, Tylor asserts that the human mind and its capabilities are the same globally, despite a particular society’s stage in social evolution.[8] This means that a hunter-gatherer society would possess the same amount of intelligence as an advanced industrial society. The difference, Tylor asserts, is education, which he considers the cumulative knowledge and methodology that takes thousands of years to acquire. Tylor often likens primitive cultures to “children”, and sees culture and the mind of humans as progressive. His work was a refutation of the theory of social degeneration, which was popular at the time.[4] At the end of Primitive Culture, Tylor writes, “The science of culture is essentially a reformers' science.”

Biological arguments for racism may have been common before 1859, but they increased by orders of magnitude following the acceptance of evolutionary theory.
—Stephen Jay Gould

I would argue that Darwin's interpretation of the evidence of evolution (as it applied to ideas about "races") was more influenced by prevailing political and cultural ideology than the other way around.

Mike, O'Henry clearly said that "Darwin's interpretation of the evidence of evolution (as it applied to ideas about "races") was more influenced by prevailing political and cultural ideology than the other way around." You didn't quote the pertinent part.

This is the most intriguing of all your quotes since,
1. It doesn't actually address or say anything about evolution.

So I did some more checking:
2. I just downloaded the free kindle version of Sanger's book, Woman and the New Race (http://www.amazon.com/Woman-New-Race-ebook/dp/B000JQV0RW/ref=sr_1_2?ie=UTF8&qid=1333116696&sr=8-2). The quote is found on pg 30 of the Kindle edition, in ch 5: "The wickedness of creating large families." In this chapter she describes the deplorable situation of (Pre-Depression era) large families. Both on the family (poverty, abuse, neglect, awful health outcomes, high rates of infant and child mortality with successive children) and on society (child labor, low wages, war, prostitution). She is so disgusted by the utter depravity that large families frequently seem to find themselves in, she condemns them as being worse than death, just like a Kansas basketball fan would say, "I will kill myself If Missouri wins the championship." No one is actually advocating suicide, they're just commenting on their feelings about Missouri.

3. A search for the word "infanticide" in this book produces some relevant quotes that would suggest that she isn't actually advocating infanticide:
"Women in all lands and all ages have instinctively desired family limitation. Usually this desire has been laid to economic pressure. Frequently the pressure has existed, but the driving force behind woman's aspiration toward freedom has lain deeper. It has asserted itself among the rich and among the poor, among the intelligent and the unintelligent. It has been manifested in such horrors as infanticide, child abandonment and abortion." - Sanger, Margaret (2005-08-01). Woman and the New Race (pp. 7-8). Public Domain Books. Kindle Edition.
"It is apparent that nothing short of contraceptives can put an end to the horrors of abortion and infanticide." - Sanger, Margaret (2005-08-01). Woman and the New Race (p. 14). Public Domain Books. Kindle Edition.

4. Did I mention that the quote had nothing to do with evolution?