It's the late 1800's. The streets are dirt. There are a few buildings and several people milling around.
At the intersection is a young black man wearing an old baseball uniform. He's standing in front of a larger, slightly older white man. This man is standing just in front of his automobile's bumper. The automobile is nondescript. Something is about to happen. There is some significance to the outcome of this confrontation.
In the distance slightly is an older, overweight white man standing by a too-modern automobile. He appears to be a wealthy sort. He, too, is interested in this outcome. Twelve black men, dressed in an identical zoot suite, walk over to him and spread out, shoulder to shoulder, to block his view. They don't want him to see something.
The young black man puts something in his hand. Something he didn't want the old, overweight white man to see. He punches the young white man in front of him. The white man goes down. The black man walks off.
His name is Brooklyn. And so, thus, is the city named.