And this is law I will maintain

You've probably heard of The Vicar Of Bray, a 17th century Berkshire churchman of rather flexible denomination. But there's also a region of France called the Pays de Bray which in the 12th century was on an important boundary in France.

A most vulnerable territory was the Vexin in the upper Seine Valley, often an invasion route for the Capetian forces striking from Paris towards Rouen. [...] Another typical lord of the Vexin was Hugh de Gournay, the dominant lord in the Pays de Bray, whose changeability won him a reputation as ‘a man of both sides’.

I'm left wondering if there's something about places called Bray that encourages famously negotiable loyalty?

(The quote is from The Reign Of Richard Lionheart, Ralph Turner & Richard Heiser.)