Why Caesar died on the Ides of March, and some counterfactual history

Four years ago, in one of the most popular posts here, I wrote about the etymology of the "rex," the "king," that Julius Caesar supposedly wanted to become, that got him killed.

But, what are the details, beyond Shakespeare, on the actual assassination?

Caesar was indeed killed for wanting to be proclaimed rex. But, it wasn't just his idea. This piece from JSTOR reminds us that Antony, among others, thought that he needed to be proclaimed king before battling the Parthians, among other things. I don't follow Antony's reasoning; Pompey had defeated kings in the eastern Mediterranean, already. But, it's a good read for the timing of Caesar's assassination and other motives the plotters may have had. (Like the piece's author, I'm not sold on the idea of Caesar's calendrical reform being an additional motive for the plot.)

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Good counterfactual history has only one major twist, so it doesn't become something like fantasy. It also doesn't involve time travel of either people or resources.

This fits both bills.

Imagine Caesar listening to friends of his — not a Shakespearean witch or wifely dream — and not going to the Senate. Or, even more, imagine him setting up a counterplot and trap. A few midlevel ringleaders get executed after formal, but drumhead, trials. Most the upper-level folks, though, like Brutus, are brought along with Caesar on the Parthian campaign, which now does take place.

Caesar offers some commands, at a certain level, knowing that even if they still hate him, committing battlefield treason and switching sides to the Parthians is highly unlikely.

What happens? He feints a straight-on attack, then has Antony pull a Neronian move through Armenia. But that itself is a feint. The right cross, to use a boxing term, comes from Julius Caesar himself. But, it's a controlled one. It's more a right hook that aims at the Parthian rear lines in Armenia rather than heading straight to Ctesiphon. Caesar avoids Crassus' mistakes, or the ones Antony will make later. Forces reunified, the then marches down Mesopotamia while sending out peace feelers at the same time. Tied to this, he drops hints that he's had communication with Bactrian princies, no matter how untrue.

And, the Parthians agree.

Terms?

Return of Crassus' standards and other lost objects. If he's still alive, the Parthians can keep Crassus himself. 

Roman control of Mesopotamia, with promises not to fortify the east bank of the Tigris. In other words, something like Trajan's conquest. Rome controls Armenia as well, but, as in reality, under some sort of client kingdom.

An exchange of hostages to seal the deal, as was common in antiquity. And, Caesar's hostages to the Parthians are some of the top-level plotters, especially ones he offered the command option and had them reject.

On return to Rome, he notes that he can offer hostages to German tribes as well.

Speaking of?

Remember that the Roman frontier in the north central part of the Empire was NOT on the Danube at this time. Presumably, Caesar would have done what happened in Augustan times. But, would Parthian kings look to have allied with German tribespeople? Could they even have physically made such a connection?