I have been using the fr ee trial to ProQuest and i think I found my family as FPOC in the 1860 Federal census schedule for Louisville, Kentucky. I know that is where they are found in 1870.

I need help to determine if they were always free and if not how they became free. What records are available to help in this search?
What suggestions do you have as to where I go from here?

Many advanced thanks to all replies.
Stephen J Dinkins