Shakespeare based the story of Julius Caesar on

'...He would be crown'd.
How that may change his nature, there's the question
It is the bright day that brings forth the adder.
And that craves wary walking...'
According to this passage, the crowning of Julius Caesar is

In Julius Caesar, one occasion when the misunderstanding of the ordinary people of Rome caused a big problem was

"O Julius Caesar, thou are mighty yet
Thy spirit walks abroad."

Based on Shakespeare's Julius Caesar, the statement above is

Caesar's ghost appears to Brutus