Just after the civil war and slavery was abolished...?

Black people were considered "Freedmen" and given their "freedom" which obviously was still a huge struggle being there were Jim Crowe laws and the former confederacy never respected the laws. My question is, after slavery was abolished, were blacks considered American Citizens? I should know this but I'm having a brain fart, I'm arguing in my paper that the south wouldn't respect their rights but they wouldn't of had "rights" had they not been citizens. I'm just curious as to when the former slaves were given citizenship, 13th, 14th, 15th amendment? I can't remember, thanks!