The story of the pyramids being built by slaves came from the Greeks who came from a culture that freely used slave labour for all large construction projects.
There’s no physical evidence at Giza of the sort of facilities that would be built to control a large number of slaves, nor are there any signs of large numbers of soldiers or other security, nor of the weapons they’d be using.
So then best explanation is that the labour force was conscripted from the local population as part of a form of state intervention- keeping them fed and occupied during the annual flood season when the fields were under water.
There are a number of finds showing how men were put into units of ten and these units were grouped into four as a ‘zau’. We even know from painted inscriptions on some of the blocks in the Red Pyramid at Dahsur and the Great Pyramid itself that these work teams had names that translate as Khufu : Endurance, Khufu : Perfection Gang and Khufu : Green Gang amongst others. Similar finds have been made at the river port at Wadi el-Jarf which supplies materials such as Tura limestone, copper and Aswan granite to the Giza complex.
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