Pardon my lack of knowledge on a significant topic, but I very much need clarification?

Hello, I am sheepishly finding it hard to clarify the Democratic National Convention that had great standing between 1967-69.The convention itself was in Chicago in 1968 and pertained to abolishing the injustice of the time which kept men and women African Americans in the deep south from being allowed their god-given right to vote. I have sought many sources for layman's terms on this noteworthy milestone in history but unfortunately I cannot make sense of the convention. Perhaps my learning disability (I was diagnosed as a child by numerous experts with sensory processing disorder) perhaps this has something to do with my never failing lack of comprehension to "link" important historical events to comprehend them, I am not sure but I am struggling with this and very much would be greatly blessed if you have a sturdy understanding of these events I mentioned and would kindly explain to me in simple, child like terms these events or perhaps even just recommending a link to me to go to would be more than wonderful. Thank you Kindly!