Antonio is portrayed as a melancholy character from the outset of the play. In the first scene, Antonio's friends, Salarino and Solanio, insist that Antonio is upset and depressed about his ships. Antonio is a wealthy merchant whose money is invested in his ships.
It depends whether you are writing a fiction book, say for example you a writing a book on the Victorians, it was a fact file, you would have to use events from real life i.e the death of Queen Victoria<span />