Yes, most European countries had slavery in one form or another. The difference in the USA is that a large portion of our country is descended from those slaves. I think France was more distant from it, if you will.
I'm always very careful not to condemn my progenitors. Judging the past through the lens of modern culture generally means you cannot see how, perhaps, their culture was healthier in some ways that ours. Additionally, 100 years from now, they will most likely think similar things of us.