Of course even in his time the audience already knew
Caesar was stabbed to death on the Ides of March, but the stabbing was not the climax of the play. Heck, Caesar isn't even the main character, despite the title. No, the lead is Brutus, only Brutus, the guy who chose wrong and paid for it with death, and we are made to feel that it wasn't his fault. By the time he asked his deputy to hold the sword so that he could run on it and kill himself, I had that tingle that reminded me of reading the chapter in which Ned Stark was beheaded. Oh you good, noble, stupid, heroic, exasperating man! Damn you, Shakespeare!
Sometimes I wonder if he actually preferred writing historical plays than the more conventional comedies and tragedies. In historical plays he could fully unleash his power of ... AMBIGUOUS CHARACTERS! In historical plays he was much less bound by the labels of good guys, bad guys, and a moral to take home with ya conventions and expectations. He could do whatever he wanted with history, except the recent history that would affect his relationship with the Crown. The symmetry of madness and revenge in Titus Andronicus. The hero we despise in Coriolanus. No wonder history is the place to learn the real nature of people. No wonder those who immersed in history (like Shakespeare and GRRM) can become truly ruthless to stale sentimentality.
I often think of Coriolanus recently, and civilization's relationship with violence and war, and masculinity and it symbols, and of course "the people", aka "the mob" sometimes. "The mob" also looms large in Julius Caesar. One of the most poignant and scary and funny --- all at once --- scenes is Mark Antony manipulating public opinion. It gave me the chills. What's more, he mocks them but he never judges! Who does that? Who else can do that?!
On to sequel, Antony and Cleopatra.