From Genesis 9:20-27:
And Noah began to be an husbandman, and he planted a vineyard:
And he drank of the wine, and was drunken; and he was uncovered within his tent.
And Ham, the father of Canaan, saw the nakedness of his father, and told his two brethren without.
And Shem and Japheth took a garment, and laid it upon both their shoulders, and went backward, and covered the nakedness of their father; and their faces were backward, and they saw not their father's nakedness.
And Noah awoke from his wine, and knew what his younger son had done unto him.
And he said, Cursed be Canaan; a servant of servants shall he be unto his brethren.
And he said, Blessed be the LORD God of Shem; and Canaan shall be his servant.
God shall enlarge Japheth, and he shall dwell in the tents of Shem; and Canaan shall be his servant.
The King James Bible

For any fundamentalist Christian living in Western Europe up until the 20th Century, this was proof that not only were certain races inferior, but were condemed to slavery by Noah himself. God lets this pass, and Noah dies at the age of 950, 300 years after he condemed Ham's posterity into slavery (Genesis 9:28-29).

This myth was perpetuated by John Speke, a self made explorer from 19th Century England. In the 1850's he was determined to reach the source of the Nile River by boat, an impossible task. His second attempt lead him to the outskirts of Rwanda, where several tribes told him of the Hutu and the Tutsi people. The Tutsi, the leaders of Rwanda at the time, were described to him as tall, fair skinned and had small noses (a status symbol in Western Europe at the time), and the the Hutu as darker, shorter and had broader noses. Upon his return to England, Speke wrote several books about the Tutsi and the Hutu, and how the superior Tutsi commanded over the pathetic Hutus, and thus the Hutu were fulfilling their Hamitic roles, as laid out in the Old Testament. The atrocities of 1994 in Rwanda can be traced to the reenforcement of the Hamitic Myth.
The problem with the Hamitic Myth is that, according to the Bible, all of man came from Noah's sons, the Semites from Shem, the Japhites from Japheth, and the Hamitic from Ham. If this is true, and given the amount of racial and ethinic mixing in the world, a vast majority of the world is in some way Hamitic, excluding the very isolated cultures. Thus, we are all slaves. Most proponents of the myth over look this. However, most proponents of the myth tend to be people and groups such as the Ku Klux Klan, prominent creationists affiliated with Bob Jones University, and Holocaust revisionists.

Some info aquired from: