It was complicated. It was a constitutional monarchy at the time, and killing the king was at least one sub-revolution away. Seriously, there were many, many ways he could have avoided being executed. The Revolutions podcast has a decent summary of all of it, including Louis XVI’s many mis-calculations and stupid PR mistakes. If you can call “a summary” 20 hours worth of podcast.

They were at war with half of Europe though, and directly threatened by the Austrian army, amongst others.

Much like the Tsars and Charles I and James I, the French monarchs of the time seem determined to escalate until it got them killed.

Modern billionaires could probably do with some history lessons.

You’re right, it’s like something that did not happen in their lifetimes will not happen ever.

To be fair to old Louis though, he did learn from the English civil war: he read Hume’s History of England and was well aware of how Charles I got killed. He tried very hard not to be as inflexible. So instead he got killed for going with the wind and saying yes too often, to the wrong people. And trying to flee, which was really un-patriotic, completely sank the legitimacy of the constitutional monarchy, and opened the door for the radicals.

The song was written in April 1792 in the context of the declaration of war from France to Austria.

The then very recent constitutional monarchy fell in August.

The king trial began in November and even then, although death was requested by some, it was not an evidence yet.

Death was voted with a small majority in January.