This isn't a version of the "Pharaoh" I sing.
(http://www.mudcat.org/detail_pf.cfm?messages__Message_ID=14016 )
Rather it's based on a spiritual from the Georgia Sea Islands.
(See http://ctl.du.edu/spirituals/freedom/source.cfm .)
As far as I know, it was first introduced to the world on a recording put out by New World records called "Georgia Sea Islands Songs" back in the mid-70s as part of a project to collect American music for the American Bicentennial. (Remember the bicentennial?!) The liner notes are available on-line: http://www.newworldrecords.org/liner_notes/80278.pdf.

To quote the relevant part of the liner notes (by Alan Lomax):

Moses

John Davis, leader; Peter Davis, Bessie Jones, Henry Morrison, and Willis Proctor. Group B.

I asked John Davis if he knew "Go Down, Moses," and he replied, scornfully, "Why, everybody know that. Here's one everybody don't know." He looked down. The silence gathered. Then he began to sing in a hoarse whisper, as if he was talking in a graveyard hideout of run-away slaves. His text is full of the cryptic language of the freedom movement: Harriet Tubman and other "conductors" on the Underground Railway were called Moses; the chariot was a symbol of escape into heaven and at times of the Underground Railway; horses running, the heavenly river rolling, and the angels moaning presaged rebellion or war. None of this was made specific by John and Peter and the other singers, but they seemed to voice it. In no other song they sang was there so much passionate assenting-groans and aha's from Peter's bass, cooing approval from the tenor, moaning in the background when the angels were moaning. For me this is the spiritual at its noblest, black singing style at its finest; and I am certain that everything was completely improvised in a performance that arose immediately in response to my query.

Moses, Moses, don't you let King Pharaoh overtake you, (3 times)
In some lonesome graveyard.

Hm, hm, I hear the chariot comin', (3 times)
In some lonesome graveyard.

Moses, Moses, I hear the horses runnin', (3 times)
In some lonesome graveyard.

Hm, hm, I hear Jordan rollin', (3 times)
In some lonesome graveyard.

Mother, mother, don't you let your daughter condemn you, (3 times)
In some lonesome graveyard.

Hm, hm, I hear the angels moaning, (3 times)
In some lonesome graveyard.

Jordan, Jordan, let the children over, (3 times)
In some lonesome graveyard.



--Charlie Baum