At Versailles, a few centimetres of red lacquer told every man in the room where he stood.

At Versailles, you could tell a man’s standing without hearing his name.

You only had to look down.

Louis XIV, the Sun King, understood that a king does not need to command a room if the room is dressing for him. He gathered the most powerful nobles of France under one roof and taught them to compete for his approval.

Colour was one of his quietest tools.

The red heel, le talon rouge, was costly to make and worn at court as a mark of privilege. Accounts differ on who first wore it. What is clear is how Louis used it: a red heel was granted, not simply bought. To wear one was to be admitted. To lose the right was to be quietly removed from the room.

Louis wore them himself, lifted and lacquered, with tiny painted scenes of his victories on the heel.

The fashion historian Kimberly Chrisman-Campbell calls the red heel a form of fashion as social control. No guard was needed and no law was read aloud. A man looked at his shoes each morning and remembered who allowed him to stand there.

Every room that matters still has its codes. They are rarely written down. They are noticed by the people who belong, and, more tellingly, by the people hoping to.

That is the world of Chapter II of Atelier Cavalier, which follows a young man trying to break into London’s most exclusive members’ club. Nobody hands him the rules. He learns them as courtiers did, by watching what the established men wear.

The Pillarbox sock belongs to that world. It takes its name from the red of the British street, a colour that has stood on corners for over a century and never needed explaining. Knitted by hand in fine cotton lisle (fil d’Écosse) by a family-run maison in Italy, it carries the same idea Versailles did: it does not announce itself. It is there for those who know where to look.

At Versailles, the red heel was a permission slip.

Today, a red sock is something gentler: a private signal that you chose it, and are quite comfortable being seen.