[stylin19a]

not in the beginning...they were indentured servants.

http://www.pbs.org/wgbh/aia/part1/1narr3.html

[caveat emptor]

not in the beginning...they were indentured servants.

Thanks, I didn't know that. But it didn't last long.

From your linked article:
In 1641, Massachusetts became the first colony to legally recognize slavery. Other states, such as Virginia, followed. In 1662, Virginia decided all children born in the colony to a slave mother would be enslaved. Slavery was not only a life-long condition; now it could be passed, like skin color, from generation to generation.