Qutb-ud-din Aibak, Altamash, and some others were kings/emperors of the famous 'Slave Dynasty' in medieval India, prior to the coming of the Mughals. The ruled what is frequently referred to as the Delhi Sultanate. Technically speaking, they were no longer slaves when they ruled, but many of them started their careers as slaves in the service of the reigning Sultan and then, through dint of capability and personality (and probably lack of any likely-looking lads amongst the heirs) were 'elected' Sultan after the death of the incumbent. I think either the Romans or the Greeks (or the Macedonians, or am I just thinking of Mary Renault?) had examples of something similar.
As for the rest, I am tempted, but would not wish to definitely call a leader on a modern world stage a pile of kak, else I would give you an example of that kai-thingy.
cheer
the sunshine warrior
