Out came Napoleon himself, majestically upright, casting haughty glances from side to side, and with his dogs gambolling round him.'
Of course the last to appear, with lots of ceremony, is Napoleon. He is described as 'majestically upright' which suggests the way he sees himself as a king. In a society where everyone is supposed to be equal, this in itself is a betrayal and indicates his power and level of control.
The word 'upright' is also a pun as it means on two legs but also suggests morally upstanding which is very ironic. He is surrounded by the dogs who symbolise his power and terrify everyone into submission.