The vast majority of blacks are descendants of slaves, and Mr. Washington is probably among them, but there were free black men who colonized America, albeit not many. There were also black slaveholders who were quite wealthy and who owned more slaves than many of the white slaveholders. The following is a source for this interesting piece of American history.
http://www.americancivilwar.com/authors/black_slaveowners.htm
You mean there were some black people in colonial days who who voluntarily got on the boat in Africa, arrived in America as free men, and who remained free, and whose descendants remained free straight through to the end of the Civil War? Or do you mean there were some early slaves or children of the first groups of slaves who gained freedom very early on during Colonial days?