Why do we wear ties?

A tie doesn't keep you warm. It doesn't hold your shirt together. Yet a strip of cloth knotted at the throat is still one of the clearest ways to say "I'm dressed formally".

Its story starts with soldiers.

Its ancestor looked nothing like today's tie.

In the Thirty Years' War (1618–1648), Croat light cavalry fighting for the Habsburgs wore long neckerchiefs, which kept out sweat and dust and could bind a wound. French soldiers met them, and some kept the look when they went home.

By the 1650s a loose neckcloth, the cravat, had become a distinctive part of European men's dress. One that survives from the 1690s, now at the V&A, is a length of fine muslin with Venetian needle-lace ends.

The name is the strongest clue.

Oxford and other major dictionaries trace "cravat" to the French cravate, from Cravate, meaning "Croat", via German Krabat and Croatian Hrvat. In 1667 Louis XIV even formed a Croat cavalry regiment, the Royal-Cravate.

Two cautions. "Croat" was also a byword for light cavalry, and those units took in Hungarians, Serbs, Poles and others. And some scholars prefer other roots for the word. The evidence supports Croat soldiers popularising a neckcloth and lending it a name, not one moment when someone invented the tie.

Then it kept changing.

There was no single inventor. A New York tie maker patented the bias cut in the 1920s, but that changed how ties hang, not what they are for.

The job became social.

As 19th-century men's dress settled into dark, near-identical suits, the tie became a signpost of social status. For much of the 20th century it stood for respectability; only in the second half did it stop being an essential part of everyday menswear.

The cloth around our necks has changed almost completely since the 1650s. What survived is the signal: you knot a tie today not to stop the sweat or dust, but to show you have dressed for the occasion.