Blacks and Italians shared the numbers business in Harlem from as far back as the '30s. The truth is, the Italians couldn't have run it at all without using black middlemen, like Bumpy Johnson. Eventually, as the black population exploded in Harlem and numbers runners became more and more independent, they lost their need for (and fear of) the Italians all together, and went out on their own.
Everything quoted here is wrong and people should listen to what Ivy says. He actually does researche, reads books and knows his subject before he types.
