Determined - He was determined to take over Germany and kill off all the Jewish people while attempting to still have many followers and a strong army.
Confident - Hitler showed he was confident leader by acting like he had no fear which helped his followers stay true to him and not stop supporting him even though he was ruthless and unkind.
Manipulative - He manipulated everyone else into thinking that his way of taking over Germany is the right way when they shouldn't be thinking that killing millions of people is OK.
Intelligent - He is an intelligent man in a sick way but to get as far as he did with the way he did it, like killing millions of Jews to start a single race and staying sure of himself.