It happened today - May 20, 2015

History is full of spectacular events. But also things that sneak up on you. For instance on May 20 of 1940, 75 years ago today, the German Blitzkrieg broke through to the English Channel at Abbeville, precisely as the Kaiser’s armies had not at Ypres In 1914, 1915 or in spring 1918. This Nazi victory was big and everyone noticed.

The same cannot be said of the patent issued on May 20 1873 for work pants reinforced with metal rivets. And if you are tempted to retort that the world has rightly taken no notice of it since either, I should specify that this patent went to a Nevada tailor named Jacob Davis and a Bavarian-born shopkeeper and entrepreneur based in San Francisco named Levi (originally Leob) Strauss.

That’s right. Their humble and obscure-sounding patent for “Improvement in Fastening Pocket-Openings” marked the birth of blue jeans. The new sturdier garments caught on fast, and by the 1920s “Levi’s” overalls were the top-selling men’s work pants in the US. And jeans long ago ceased to be primarily a work pant. Indeed, it’s interesting how, as the U.S. got richer and richer, it became more and more of a fashion statement to dress down in work pants especially if you turned on, tuned in and dropped out of the rat race. To the point that for some three decades now you’ve been able to buy artificially “pre-distressed” jeans if your lifestyle emphatically won’t wear them out on its own.

Of course, Hitler considered Americans and their blue jeans decadent and if he’d won the Second World War they might have been chased back to the factory, farm and workshop. The sword is mightier than the pocket fastener. But in terms of their overall impact on global culture, blue jeans still mattered more than his armies’ terrifying breakthrough to the channel.