"The first African slaves to arrive in the "new world" were brought over by Christopher Columbus in 1493"
That's never been conclusively proven, and very debatable. We know Columbus had one personal African slave of his own on the 1493 voyage, but did he bring a ship load over then? Not likely, especially since he created his own mother lode of slaves from the indigenous peoples of the Caribbean. In fact, he shipped many of them back to Europe, as well as moved them around to other places in the Caribbean and South America.