Caesar is plannng to take over rome and turn it into a Dictatorship
Casca and Cinna were two of the conspirators who murdered Caesar.
death
Brutus, Marullus and Casca.
Casca sees Caesar refuse a crown offered to him by Mark Antony three times. He also sees him have an epileptic fit.
He commits suicide after the battle of Phillipi
Casca
Casca is the first to stab Caesar.
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Casca
Casca and Cinna were two of the conspirators who murdered Caesar.
Why not - that's what they were. Cassius, Brutus, Casca and so on plotted to kill Caesar at the Senate in 44BC
Casca, the others stab him then, and Brutus stabs him last.
Casca
Yes, Casca believed that the Roman people seemed to want Caesar to be king based on their enthusiastic applause and support for Caesar during the Lupercal festival. Casca thought that Caesar's ambition to be the king was driven by the people's desire for him to take the position.
By "the book Julius Caesar" I assume you mean Plutarch's Life of Caesar, one of his Parallel Lives, sometimes just called "Plutarch's Lives". (This is opposed to the PLAY Julius Caesar, written by Shakespeare, using Plutarch as a source.) In Plutarch, the first blow is struck by Casca, who stabbed Caesar in the neck, but neither mortally nor deeply.
Casca was a Roman senator and a conspirator in the plot to assassinate Julius Caesar. He played a key role in the assassination by being one of the first to stab Caesar, which ultimately led to Caesar's downfall. Casca's actions were pivotal in the events that unfolded in Shakespeare's play "Julius Caesar."
Casca says, "Speak hands for me!" By this, he means he intends to use his hands (in the murder) to express how he feels about Caesar.