I recall that many years ago, perhaps 25 or so, El Al evacuated a large number of a lost tribe of black Jews from Ethiopia. I think they got about 800 people into a 747 with the seats removed.
EDIT : Just googled it. It was called Operation Solomon and
'There has probably been as many, if not more, in the smaller upper deck of the -200
Remember El Al squeezed 1087 people onto a 747-200 back in 1991 during an evacuation from Ethiopia. It was in 1991 and 14,000 Falashas were airlifted from Ethipia to Israel.
Project Open Sky > 747-400 upper deck certification