Caesar
Kaiser
Simon Legree
absolute monarch
absolute ruler
all-powerful ruler
arrogator
autarch
autocrator
caesar
commissar
czar
czarina
despot
dictator
disciplinarian
driver
duce
emperor
hard master
martinet
monarch
oligarch
oppressor
pharaoh
slave driver
stickler
tsar
tsarina
tyrant
usurper
warlord
potentate
aristocrat
ascendency
democrat
despotism
egoist
nonentity
ruler