A Greek biographer, author and a historian, Plutarch (A.D. 46 - 119), wrote a book called Parallel Lives, in which he recounts the noble deeds and characters of Greek and Roman rulers, legislators, orators and statesmen. This book was translated by Sir Thomas North in 1579.
This translation was Shakespeare's source for his Roman plays. Shakespeare used about full passages with making some minor changes in them which would suit his story line and gave it a more dramatic effect.
In the play Julius Caesar, William Shakespeare had taken these following plots or events in various scenes almost without changing much from the translated work of Plutarch by Sir Thomas.
Act I Scene ii
The Celebration of the feast of Lupercal.
Offering of crown to Julius Caesar by Mark Anthony, which Caesar refused to accept.
Suspicion in the mind of Caesar about Cassius.
Act II Scene iii
Artemidorus giving Caesar a letter of warning.
Act III Scene i
Assassination of Julius Caesar.
Oration of Brutus in the market place.
Cassius opposed to the idea of Brutus of giving Cassius a chance to speak at the Caesar's funeral.
Act III Scene ii
Antony's funeral speech and afterward riot by the Roman people.
The escape of the conspirators.
Act III Scene iii
The murder of Cinna - the poet by the angry roman mob.
Act IV Scene iii
Cassius's meeting with Brutus and his accusation.
The Caesar's ghost appeared to Brutus.
Act V Scene i
Brutus decides that he will commit suicide if he loses the battle.
Act V Scene v
Brutus's suicide by running through the sword hold by Strato.
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