From trench coats to bomber jackets, some of our favourite action-inspired pieces from Gucci, Saint Laurent and more .

Necessity is the mother of invention, and many of the greatest innovations in menswear have been forged in the crucible of war. In fact, the eminent British fashion historian Mr James Laver believed that most of the masculine wardrobe was created with either the battlefield or the sports field in mind. There’s a good reason for this, which is that the pressure on a fashion designer to come up with a fresh-looking garment for next season’s collection is nothing compared to the pressure on a designer of military clothing, who needs to innovate in order to potentially save lives on the battlefield, in the skies above it, or at sea.

Of course, this matters to us only because the resulting clothes frequently look so good. That’s why Mr George “Beau” Brummell decided, at the turn of the 19th century, to adapt his cavalry uniform for civilian wear, and that’s why this season men are again wearing designs imbued with military history, garments such as trench coats and MA-1 jackets. Military outerwear embodies the old modernist maxim “form follows function” (you’ll want to know that this was actually minted by the American architect Mr Louis Sullivan as “form ever follows function”). Whether these garments’ origins are 19th century or 20th century, they remain the ideal collision of aesthetics and practicality.

Here, we review the latest street photography to see how men are wearing the newest versions of these venerable military designs.

In this shot, the actor, designer and man-about-town Mr Waris Ahluwalia puts the great into his greatcoat. While it’s very hard to precisely define a greatcoat, we know one when we see one, and the epaulettes, double-breasted configuration, and the fact that it extends below the knee are all distinguishing features. It’s a form familiar to soldiers for at least the past 200 years – Monsieur Napoleon Bonaparte wore a very similar garment when he made his ill-fated assault on Moscow in 1812. Short overcoats may be more practical in a world of over-heated cars, offices, restaurants and bars, but there’s no substitute for the imperial sweep of a well-cut greatcoat.

Green, brown, sand or olive drab, there’s a particular palette of colours that’s used in military clothing, from the M-65 field jacket to the British Warm. It’s a palette that includes the colour of the over-shirt being worn by the man on our left, who’s added it as an insulating layer between his shirt and his jacket. The chap on our right, however, looks more prepared for the cold, as he’s bundled up in a simple peacoat (originally a naval style – the P stands for pilot). With its storm collar and double-breasted button stance, it stands as a bulwark against wintry weather, especially if it’s combined with a substantial cashmere scarf.

The parka, which received its military stamp of approval when the US Army started to issue the M-1948 model, has been through several incarnations and has been associated with many youth subcultures (particularly the mod). Defined by its hood, its long form (which traditionally is cut so that the centre of the back hangs low, hence the name “fishtail”) and its ability to keep a man warm and dry, the parka is usually very spacious. Which is presumably why the man in this shot has accessorised his with a belt, a function of which is to hold the coat open so we can admire its detachable fleece lining and the denim jacket worn beneath it.

When it comes to sartorial one-upmanship, the winning tactic is to wear a piece of vintage clothing. Old, well-worn clothes have a depth and a substance that new pieces lack, regardless of how attractive they may be. In this case, our subject has laid his hands on a fantastic US Army jacket of unusual design; the absence of epaulettes, the slanted breast pockets and the lightweight fabric suggest this was originally designed to be worn in the tropics – it appears to be a Vietnam-era jungle jacket. Clothes from the Vietnam period have the added allure of being associated with 1960s counterculture, which was, ironically, an important part of Army life at that time.

Early last century, Mr Thomas Burberry developed a coat he initially called the “Tielocken”. The coat was made from (then) innovative gabardine cotton, which kept the wearer dry, while allowing air to circulate, unlike the rather sweaty, early rubberised, waterproof coats. Tested under the most extreme circumstances by British Army officers in WWI, it came to be known as a “trench” coat. Today Tielockens are worn by men lucky enough to be leading much more comfortable lives, but who still appreciate the trench coat’s ability to keep them dry, as well as its masculine swagger.

From the original MA-1 model to the latest Nomex CWU-45, flying jackets have always been as sought after for the way they look as for the warmth that they afford. Cut to sit on the hips, because they’re designed to be worn while seated in a cockpit, bomber jackets invariably convey an active and sporty image, and so work as well for men who are in the air or on the ground. This olive-green version contrasts well with the double denim worn beneath it, and boasts an unusually full collar, which will come into its own when winter’s cold winds start to blow.

When the leather A-1 flying jacket was introduced in 1927, few would have guessed that it represented merely the first pickings from such a rich seam of inspiration. Almost 90 years later the appeal of this garment burns as brightly as ever. As leather flight jackets evolved, they changed, although replicas of almost every iteration are still being made today. This sophisticated version of the G-1 model, which has a tan-coloured collar and waistband that contrast with the black leather, has an urban, contemporary edge. As it’s worn here with slim jeans, it’s important to note the jacket’s modern cut – an old baggy version wouldn’t have looked half as good.

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