Illustrations of history

So, Galba was acclaimed Emperor after the infamously bad Nero was declared an enemy of the state by the Senate. This was the first real succession crisis in the Roman Empire, though, and Galba was not even the first choice so much as he was the surviving choice, so naturally there was a lot of scheming and others trying to play their hand at becoming top dog.

Galba was not politically adroit or particularly charismatic - he had a tendency to rub people the wrong way. Not lethal in and of itself, but combined with the circumstances, it led to a lot of uncertainty. The Legions stationed in Germania, in particular, decided to start a civil war over who should be Emperor (naturally, they favored their own commander, Vitellius, who promised them huge rewards if they made him Emperor).

One old favorite of the Emperor Nero, a fellow named Otho, saw his chance in all the uncertainty over who was really entitled to the position of Emperor, and flattered, bribed, wheedled, and cajoled some key players in the city of Rome into taking his side, secretly, in a coup to claim the position of Emperor.

Honestly, the attempt shouldn't have worked. It was something of a comedy of errors, and they were not particularly well-placed to coup Galba in the first place. But as mentioned previously - Galba's own lack of charisma and political support worked against him, and the uncertainty was just enough to paralyze everyone who should've been involved in stopping the coup attempt. The Senate itself changed sides like, three times in one day. That's the level of confusion we're talking about.

So Otho's supporters sweep through the city, convince everyone that they've already taken over, and then, catching Galba unaware by telling him Otho's coup had failed and Otho had been killed, ambushed him and his bodyguards, killing both Galba and the man he appointed as his successor.

Otho, having come to power in a bloody and illegitimate manner, is himself overthrown by Vitellius, albeit in open combat rather than a metaphorical palace coup - and then Vitellius is overthrown and replaced by Vespasian, a general in Iudea who was loyal to Galba. 69 AD (nice) - the Year Of The Four Emperors, it was called, and the first major civil war of the Empire! What a year!

tl;dr; lackluster politician fails to stop a coup attempt, is stabbed to death on the streets of Rome.

Not as good as a PugJesus summary but the story here is wild

https://en.wikipedia.org/wiki/Galba#Mutiny_on_the_frontier_and_assassination