On April 23, 1946, Enrico Piaggio filed a patent with the Ministry of Industry and Commerce for 'a motorcycle of a rational complexity of organs and elements combined with a frame with mudguards and a casing covering the whole mechanical part'.
In less formal terms, the machine in question was called a Vespa - and this year the marque celebrates an impressive 75 years of unbroken production with close to 20 million having been sold around the world across a range of at least 50 variations on the theme.
All can be traced back to the day Piaggio came up with the idea of saving his father Rinaldo's bombed-out aero factories from demolition by converting them into production lines which would churn-out cheap transport for the masses. His vision was to do away with the oil and grime associated with motorcycling by making a runabout with an enclosed engine, no chain and protective bodywork.
Engineer Corradino D'Ascanio and designer Mario D'Este came up with the goods, and the prototype Piaggio two-wheeler was given its first airing at the Rome golf club in 1946, although it was Enrico who played the masterstroke by likening the scooter's narrow-waisted appearance to that of a wasp and coming up with the 'Vespa' name.
What was intended to be a 'revolution on wheels' initially met with a lukewarm reception, but Enrico decreed a run of 2,000 units - and by the time Gregory Peck had thrown his leg over a Vespa while squiring Audrey Hepburn in the 1958 film Roman Holiday, annual sales were topping more than 170,000.
John Wayne, Henry Fonda and Dean Martin were just some of the other Hollywood stars happy to bask in the Italian sun astride Vespas. Charlton Heston even took a break from filming Ben Hur in '59 in order to be snapped riding one while wearing a toga and, three years later, Salvador Dali daubed one with his painted signature. Now, the blue 150S model that belonged to a couple of passing art students is likely to be the most valuable Vespa in existence.
In their heyday, Vespas were also raced competitively - and, in 1980, four Vespa-mounted Frenchmen tackled the gruelling, three week, Paris-Dakar desert rally. And one even made it to the finish.
But in drizzly old Britain, with its paucity of piazzas and where cappuccinos were yet to replace a good, strong cup of builder's tea, the streamlined Vespa found its niche in Mod culture as an antidote to the rival Rockers' dirty, oil-stained Triumphs and Nortons.
The seaside resorts of Margate and Brighton became as awash with Vespas as Milan and Bologna - and, by the mid '60s, all of England's sea-front cafe owners had attuned themselves to the buzz of the engines that signalled potential trouble from the warring factions.
Within a decade, however, enthusiasm for the Vespa began to wane in Britain and Europe as the machine once considered chic, practical and fun no longer seemed quite so cool - leading to thousands of them being abandoned in sheds, garages and barns the length and breadth of the continent.
By 1990, fewer than 170 new Vespas were being sold in the UK each year. And as for second-hand ones - you could hardly give them away.
But with the new millennium seemed to come a road congestion tipping point. Suddenly, many commuters could no longer bear being trapped in traffic and a Vespa once more provided a way out. New models with electric starters, automatic gearboxes and quieter, less fussy four-stroke engines increased the appeal to novice riders, and annual production numbers soared to 58,000 in 2004, 100,000 in 2006 and passed the 200,000 mark in 2018 - amounting to 1.8 million new Vespas sold in the past decade alone.
And to mark this year's anniversary, Vespa today pulls the wraps off a special 'Giallo 75th' model in a shade of metallic yellow based on 'hues in vogue during the 1940s'.
The machine's side panels and front mudguard carry a subtle number 75, with other special features being a nubuck leather saddle, grey-painted wheel rims and a plethora of chromed parts.
The rear luggage rack, meanwhile, holds a leather bag in the shape of a vintage Vespa spare wheel holder (a sure-fire target for the light-fingered) and there's 'anniversary special' badging behind the leg shield. Each one will be supplied with a 'welcome kit' comprising an Italian scarf, a vintage steel Vespa plate, a dedicated owner's book and a set of postcards charting the marque's history.
Speaking of which, anyone who thinks a vintage Vespa is just an old bike that no one would want might be surprised to discover that an original from the late 1940s can now be worth up to £90,000... but that's another story.