It wasn't just in the US that black people started the EMT services. In Britain, the Harrow and Wealdston train crash in 1952 was the worst peacetime rail disaster in UK history(112 dead, 340 wounded). A United States Air Force medical unit was among the first responders, and while most ambulances at the time(including this incident) just picked up anyone injured and rushed them to the hospital, the USAF people recognized that things were so bad this should be handled like battlefield medicine, treating and triaging on-site. 7 doctors and, crucially, 1 nurse, Abbie Sweetwine made up the USAF medical unit.
While ambulances were rushing off with "walking wounded" who had made it out of the accident first, the more seriously injured were still being dragged from the wreckage. The doctors who had rushed over with whatever they happened to grab treated those on-site. Meanwhile, Lt. Sweetwine handled triage and recorded what treatments had been performed by writing on the patients with lipstick and directed the returning ambulances which patients to take back to hospitals next. This was crucial for saving lives, and when the various UK organizations were figuring out how to make sure this sort of disaster didn't happen again, the role of ambulances as actual medical providers rather than as a fancy taxi service was one of the big realizations. It wasn't a wholly new concept, but news articles and pictures showing doctors on-site, crucially with Abbie Sweetwine following up with patients and covering basic care, gave a solid basis that the NHS could model it's Paramedic system after.
And Abbie Sweetwine was black. This was almost unheard of for the time, a black woman serving with the USAF, and the impact of a black woman being lauded for heroism throughout the UK on your average Joes cannot be overstated. She basically just did her job, continued doing it for the next few decades, and retired to her home state of Florida with some unusual medals on her wall, but she also changed a country and that's not something most people can say.
(source, please click through for a better writer than me tackling this)