Socialist Bob Dylan guy has a solid timeline, but nothing spectacular (he's Spanish, but was adopted by black American parents stationed in Spain and then moved to Florida, so he considers himself half black, half Cuban):
KNOW YOUR HISTORY: Memorial Day was started by former slaves on May, 1, 1865 in Charleston, SC to honor 257 dead Union Soldiers who had been buried in a mass grave in a Confederate prison camp. They dug up the bodies and worked for 2 weeks to give them a proper burial as gratitude for fighting for their freedom. They then held a parade of 10,000 people led by 2,800 Black children where they marched, sang and celebrated.
Thanks to Abstrakt Goldsmith for this nugget of history that most of us never learned in school.