Another evidence for the fact that runaway slaves were not usually ideologically motivated individuals rebelling against a system and were merely helpless people trying to get out of a miserable situation, can be seen in the prevalence of ‘passing’. Passing’ or trying to pass as white, has a long history in the African American community. As these advertisements in 19th century newspapers show, lighter skinned ‘mulatto’ slaves would often seek freedom from slavery through ‘passing’:
“Detained in jail, Maria; pretending herself free; round face, clear white complexion.” — P. BAYHI, Captain of the Watch.
“Ranaway, a bright mulatto woman, named Julia, about twenty-five years old. She is nearly white, and very likely may attempt to pass for white. She is a good seamstress, dresses fine, and can read a little. $200 reward, if caught in any Free State, and put into any good jail in Kentucky or Tennessee.”
Harriet Jacob’s owner also made references to the fact that she was light skinned and that her hair could be combed straight and that she dressed finely, probably intending to relate his fear that she would get away through ‘passing’.
The ‘mulatto’ was usually the product of a union between a white man and his captive African-American slave woman who lacked the power to resist his sexual advances. In the pre-civil war south, it was common for slave owners to use their female slave women sexually.
The fate of the resultant children depended upon the extent to which their physical features represented their European or their African ancestry. If the child was white enough, it would be possible for it to be brought into the family, if it was too dark to pass off as a Caucasian person, it would remain a slave.
 The New Orleans Bee, July 4, 1837 quoted in Child, 1860
 The Republican Banner and Nashville Whig, Tenn., July 14, 1849 quoted in Child, 1860