and the best way to start it is with a 16th century joke:

"a man did ride to the market with two bushels of wheat".

But because his horse shouldn't carry a heavy load,

he carried the wheat on his own neck, but still rode the horse.

I'm not saying it's a great 16th century joke.

But that is one of the Merry Tales of the Mad-Men of Gotam,

a 16th-century compilation of stories

insulting the intelligence of the people of this town.

Which is pronounced "goat-um".

The jokes compiled in that book date back centuries more,

and while the details have changed with retellings over the years,

the story behind them goes like this:

Back in the early 13th century, King John –

the King John from the tales of Robin Hood –

wanted to travel through this town.

The locals were worried, because if the King travelled on a road,

it would become a public highway, and they didn't want that.

Or in other retellings, the King wanted to build a hunting lodge somewhere nearby,

and the locals would have to pay for it.

So whenever royal messengers arrived in Gotham, they found the locals doing something ridiculous.

They tried to capture a cuckoo by building a circular hedge around it,

and when the bird flew away,

decided they just hadn't built the hedge high enough.

They tried to kill an eel by drowning it.

Back then, "madness" was thought to be contagious.

If the King was to visit this town, then who knows:

he might catch whatever they had.

The king stayed away, and the locals won.

So the full legend tells the tale of a wily group of people who outwitted the King…

but who also became known as a village of fools in the process.

They were both the Wise Men of Gotham and the Mad Men of Gotham.

Centuries later, in the early 1800s, there was an American writer called Washington Irving.

He's best known now for writing the Legend of Sleepy Hollow,

but among many other things, he was a satirist,

and in one of his early works he refers to New York City as Gotham.

Now, I tracked down that bit of writing, and I can't understand it.

I don't know any of the context.

I don't know if he's calling the citizens of New York dim, or clever, or both.

But the nickname he gave New York stuck around in the public consciousness –

and it was written down, so at some point, "Goat-um" became "Goth-am".

More than a century after that, when comic book writer Bill Finger

was looking for a name for Batman's fictional town,

he flipped through the New York City phone book,

spotted “Gotham Jewellers”, and thought: that's perfect.

So now we have Gotham City.

If one link in that chain had broken,

through 13th-century legend, to 16th-century insult book,

to 19th-century writer, to 20th-century phone book flip,

if one of those small events hadn't happened,

Batman would live somewhere else.