Mention of Nimrod in the Bible is rather limited. According to the "documentary hypothesis" of the Bible's origin, the Jahwist writer(s) make the earliest mention of Nimrod. He is described as the son of Cush, grandson of Ham, great-grandson of Noah; and as "a mighty one on the earth" and "a mighty hunter before the Lord". He also appears in the First Book of Chronicles and in the Book of Micah.
I distinctly remember outdoors mags when I was a kid as using Nimrod in the sense of great hunter. The whole Wiki entry is interesting and you can read it here. If Nimrod was the grandson of Ham, then he was black, as in the Bible Ham is the progenitor of the black races (the Ethiopians are Hamitic).