Why are the Civil War(13,14 and 15) amendments needed?

http://library.thinkquest.org/J0112391/civil_war_amendments.htm

So these amendments insured our rights as citizens?

Yes, but these particular amendments ensured the rights of a specific group of people who hadn't had rights before the Civil War. Which group was that?

Slaves/African Americans?

Yes.

Thank you! :-D

You're welcome.