Especially since Steven Spielberg's Lincoln is currently in cinemas across the nation, we remember the Emancipation Proclamation. 150 years ago it was an executive order issued by President Lincoln that proclaimed that slaves that were held in the territory controlled by the Confederate States of America were freed. Now granted Confederate held territory not under the control of the Union this order didn't have any effect. It was on Confederate territory that were held by Union forces during the Civil War where this order took effect.
I'm only noting that because there are those out there who continue to argue that President Lincoln never freed any slaves. Surely there are others out there who are better able to argue that position that I'm able to at the moment.
In looking for materials on this subject I found this Forbes posting that asked one question, "150 Years After The Emancipation Proclamation, Are We Free?" It isn't so much an article that talks about equality amongst various "minority" groups in America as much as it is a philosophical argument about the freedom of the individual and its relationship with government. It notes the positives of the Proclamation even if while a segment of America's population were no longer enslaved they still had to fight for their freedom years after that fact.
Also you can read an article about the Proclamation courtesy of the Nation Archives.