Jacques-Louis David

She's the one who ordered this, according to Wikipedia — not just a sitter but his working partner, translating English chemistry into French and drawing the plates for his book. He made his money collecting taxes, which is what got him executed a few years after this was painted.

The story is out of Plato: Socrates convicted of corrupting the young, handed poison, and choosing to keep talking rather than run. It turned up a couple of years before the Revolution, and people at the time apparently read a man refusing to shut up for the state as being about a lot more than Athens.

It's the story where the lover only ever comes at night and she's forbidden to know who he is. Most painters gave her a beautiful boy; here, according to the museum, he's deliberately an awkward teenager very pleased with himself, taken partly from an old Greek poem that calls him a mean-spirited brat. Painted in exile in Brussels, after the empire he'd spent years working for collapsed.

A Scottish aristocrat who admired him ordered this, from what I can find — not the man in it, who is doubted to have sat for it at all. The pitch being made is the ruler up all night writing the law code rather than out winning battles, which was a useful thing to be selling by then.